diff --git a/.gitattributes b/.gitattributes
index 35a3066ee9c..ccb9bc4d4b5 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -18,7 +18,6 @@
 *.js text
 *.hmtl text
 *.bib text
-*.sh text
 *.css text
 *.ui text
 *.qrc text
@@ -36,6 +35,7 @@
 *.pdb text
 
 # Declare files that will always have LF line endings on checkout.
+*.sh text eol=lf
 Documentation/Doxyfile text eol=lf
 Documentation/pkglist_filter text eol=lf
 Installation/update_CHANGES text eol=lf
diff --git a/.travis.yml b/.travis.yml
index 67ef61cbf57..2c2fe62d3f4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -49,10 +49,10 @@ env:
     - PACKAGE='Surface_mesh_parameterization Surface_mesh_segmentation Surface_mesh_shortest_path '
     - PACKAGE='Surface_mesh_simplification Surface_mesh_skeletonization Surface_mesh_topology '
     - PACKAGE='Surface_mesher Surface_sweep_2 TDS_2 '
-    - PACKAGE='TDS_3 Testsuite Three '
-    - PACKAGE='Triangulation Triangulation_2 Triangulation_3 '
-    - PACKAGE='Union_find Visibility_2 Voronoi_diagram_2 '
-    - PACKAGE='wininst '
+    - PACKAGE='TDS_3 Testsuite Tetrahedral_remeshing '
+    - PACKAGE='Three Triangulation Triangulation_2 '
+    - PACKAGE='Triangulation_3 Union_find Visibility_2 '
+    - PACKAGE='Voronoi_diagram_2 wininst '
 compiler: clang
 install:
   - echo "$PWD"
diff --git a/.travis/packages.txt b/.travis/packages.txt
index 69e4f85c73a..6e75cd0ad14 100644
--- a/.travis/packages.txt
+++ b/.travis/packages.txt
@@ -129,6 +129,7 @@ Surface_sweep_2
 TDS_2
 TDS_3
 Testsuite
+Tetrahedral_remeshing
 Three
 Triangulation
 Triangulation_2
diff --git a/AABB_tree/demo/AABB_tree/Scene.cpp b/AABB_tree/demo/AABB_tree/Scene.cpp
index b28368d39a6..69ba683a21b 100644
--- a/AABB_tree/demo/AABB_tree/Scene.cpp
+++ b/AABB_tree/demo/AABB_tree/Scene.cpp
@@ -45,8 +45,7 @@ Scene::Scene()
     m_blue_ramp.build_blue();
     m_max_distance_function = (FT)0.0;
     texture = new Texture(m_grid_size,m_grid_size);
-    startTimer(0);
-    ready_to_cut = false;
+    ready_to_cut = true;
     are_buffers_initialized = false;
     gl_init = false;
 
@@ -519,6 +518,7 @@ void Scene::changed()
         compute_elements(_UNSIGNED);
     else
         compute_elements(_SIGNED);
+    ready_to_cut=false;
     are_buffers_initialized = false;
 
 }
@@ -1226,12 +1226,16 @@ void Scene::cut_segment_plane()
     m_cut_plane = CUT_SEGMENTS;
     changed();
 }
+void Scene::updateCutPlane()
+{
+  ready_to_cut = true;
+       QTimer::singleShot(0,this,SLOT(cutting_plane()));
+}
 
 void Scene::cutting_plane(bool override)
 {
     if(ready_to_cut || override)
     {
-        ready_to_cut = false;
         switch( m_cut_plane )
         {
         case UNSIGNED_FACETS:
@@ -1304,13 +1308,13 @@ void Scene::refine_loop()
 
 void Scene::activate_cutting_plane()
 {
-    connect(m_frame, SIGNAL(modified()), this, SLOT(cutting_plane()));
+    connect(m_frame, SIGNAL(modified()), this, SLOT(updateCutPlane()));
     m_view_plane = true;
 }
 
 void Scene::deactivate_cutting_plane()
 {
-    disconnect(m_frame, SIGNAL(modified()), this, SLOT(cutting_plane()));
+    disconnect(m_frame, SIGNAL(modified()), this, SLOT(updateCutPlane()));
     m_view_plane = false;
 }
 void Scene::initGL()
@@ -1326,10 +1330,3 @@ void Scene::initGL()
     compile_shaders();
     gl_init = true;
 }
-
-void Scene::timerEvent(QTimerEvent *)
-{
-    if(manipulatedFrame()->isSpinning())
-        set_fast_distance(true);
-    ready_to_cut = true;
-}
diff --git a/AABB_tree/demo/AABB_tree/Scene.h b/AABB_tree/demo/AABB_tree/Scene.h
index 4e9fabd735b..95ea74cdc33 100644
--- a/AABB_tree/demo/AABB_tree/Scene.h
+++ b/AABB_tree/demo/AABB_tree/Scene.h
@@ -173,6 +173,8 @@ private:
     void attrib_buffers(CGAL::QGLViewer*);
     void compile_shaders();
     void compute_texture(int, int, Color_ramp, Color_ramp);
+private slots:
+    void updateCutPlane();
 
 public:
     // file menu
@@ -251,8 +253,6 @@ public:
     void activate_cutting_plane();
     void deactivate_cutting_plane();
 
-    //timer sends a top when all the events are finished
-    void timerEvent(QTimerEvent *);
 
 
 public slots:
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_X_trapezoid.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_X_trapezoid.h
index a52f91db9d2..e7202ffe935 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_X_trapezoid.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_X_trapezoid.h
@@ -142,7 +142,7 @@ public:
 
  private:
 
-  Trpz_parameter_space* ptr() const { return (Trpz_parameter_space*)(PTR.p);  }
+  Trpz_parameter_space* ptr() const { return (Trpz_parameter_space*)(PTR);  }
 
 
 #ifndef CGAL_TD_DEBUG
@@ -323,7 +323,7 @@ public:
   {
     //define the initial trapezoid: left, right, btm, top are at infinity.
     // its type is TD_TRAPEZOID ,it is on all boundaries, and has no neighbours
-    PTR.p = new Trpz_parameter_space
+    PTR = new Trpz_parameter_space
       (Traits::vtx_at_left_infinity(),
        Traits::vtx_at_right_infinity(),
        Traits::he_at_bottom_infinity(),
@@ -353,7 +353,7 @@ public:
     else //tp == TD_VERTEX
       type_flag |= CGAL_TD_VERTEX;
 
-    PTR.p = new Trpz_parameter_space
+    PTR = new Trpz_parameter_space
       (l, r, b, t, type_flag | boundness_flag, lb, lt, rb, rt);
     m_dag_node = node;
   }
@@ -370,7 +370,7 @@ public:
                   Self* rb = 0, Self* rt = 0,
                   Dag_node* node = 0)
   {
-    PTR.p = new Trpz_parameter_space
+    PTR = new Trpz_parameter_space
       (l ? *l : Traits::vtx_at_left_infinity(),
        r ? *r : Traits::vtx_at_right_infinity(),
        b ? *b : Traits::he_at_bottom_infinity(),
@@ -436,7 +436,7 @@ public:
   /*! Access the trapezoid id (PTR). */
   CGAL_TD_INLINE unsigned long id() const
     {
-      return (unsigned long) PTR.p;
+      return (unsigned long) PTR;
     }
 
   /*! Access trapezoid left. */
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_edge.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_edge.h
index 2cdeee6bca5..61259f33547 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_edge.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_edge.h
@@ -135,7 +135,7 @@ public:
 
  private:
 
-  Data* ptr() const { return (Data*)(PTR.p);  }
+  Data* ptr() const { return (Data*)(PTR);  }
 
 
 #ifndef CGAL_TD_DEBUG
@@ -194,7 +194,7 @@ public:
   Td_active_edge ()
   {
 
-    PTR.p = new Data
+    PTR = new Data
       (Traits::empty_he_handle(), Td_map_item(0), nullptr);
     //m_dag_node = nullptr;
   }
@@ -204,7 +204,7 @@ public:
                   boost::optional<Td_map_item&> next = boost::none)
   {
 
-    PTR.p = new Data(he, (next) ? *next : Td_map_item(0), node);
+    PTR = new Data(he, (next) ? *next : Td_map_item(0), node);
     //m_dag_node = node;
   }
 
@@ -261,7 +261,7 @@ public:
   /*! Access the trapezoid id (PTR). */
   CGAL_TD_INLINE unsigned long id() const
     {
-      return (unsigned long) PTR.p;
+      return (unsigned long) PTR;
     }
 
 
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_fictitious_vertex.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_fictitious_vertex.h
index 6bfb3d5e6f2..b75de1b9d97 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_fictitious_vertex.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_fictitious_vertex.h
@@ -129,7 +129,7 @@ public:
   };
 
 private:
-  Data* ptr() const { return (Data*)(PTR.p); }
+  Data* ptr() const { return (Data*)(PTR); }
 
   Curve_end vtx_to_ce(Vertex_const_handle v) const
   {
@@ -180,14 +180,14 @@ public:
 
   Td_active_fictitious_vertex()
   {
-    PTR.p = new Data(Traits::empty_vtx_handle(), Traits::empty_he_handle(), nullptr);
+    PTR = new Data(Traits::empty_vtx_handle(), Traits::empty_he_handle(), nullptr);
   }
 
   /*! Constructor given Vertex & Halfedge handles. */
   Td_active_fictitious_vertex(Vertex_const_handle v,
                               Halfedge_const_handle cw_he,
                               Dag_node* node = 0)
-  { PTR.p = new Data(v, cw_he, node); }
+  { PTR = new Data(v, cw_he, node); }
 
 
   /*! Copy constructor. */
@@ -224,7 +224,7 @@ public:
   inline const Self& self() const { return *this; }
 
   /*! Access the trapezoid id (PTR). */
-  inline unsigned long id() const { return (unsigned long) PTR.p; }
+  inline unsigned long id() const { return (unsigned long) PTR; }
 
   /*! Access trapezoid left.
    *   filters out the infinite case which returns predefined dummy values
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_trapezoid.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_trapezoid.h
index 2b565adba74..8b92b739626 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_trapezoid.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_trapezoid.h
@@ -144,7 +144,7 @@ public:
 
  private:
 
-  Data* ptr() const { return (Data*)(PTR.p); }
+  Data* ptr() const { return (Data*)(PTR); }
 
 public:
 
@@ -255,7 +255,7 @@ private:
   {
     //define the initial trapezoid: left, right, btm, top are at infinity.
     // has no neighbours
-    PTR.p = new Data
+    PTR = new Data
       (Traits::empty_vtx_handle(),
        Traits::empty_vtx_handle(),
        Traits::empty_he_handle(),
@@ -274,7 +274,7 @@ private:
                   boost::optional<Td_map_item&> rt = boost::none,
                   Dag_node* node = 0)
   {
-    PTR.p = new Data (l, r, b, t, (lb) ? *lb : Td_map_item(0), (lt) ? *lt : Td_map_item(0),
+    PTR = new Data (l, r, b, t, (lb) ? *lb : Td_map_item(0), (lt) ? *lt : Td_map_item(0),
                    (rb) ? *rb : Td_map_item(0), (rt) ? *rt : Td_map_item(0), node);
     //m_dag_node = node;
   }
@@ -332,7 +332,7 @@ private:
   /*! Access the trapezoid id (PTR). */
   inline unsigned long id() const
   {
-    return (unsigned long) PTR.p;
+    return (unsigned long) PTR;
   }
 
   /*! Access trapezoid left.
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_vertex.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_vertex.h
index de4000ebfd9..3b3e86aa0c6 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_vertex.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_active_vertex.h
@@ -134,7 +134,7 @@ public:
   };
 
 private:
-  Data* ptr() const { return (Data*)(PTR.p); }
+  Data* ptr() const { return (Data*)(PTR); }
 
   Curve_end vtx_to_ce(Vertex_const_handle v) const
   {
@@ -184,14 +184,14 @@ public:
 
   Td_active_vertex()
   {
-    PTR.p = new Data(Traits::empty_vtx_handle(), Traits::empty_he_handle(), nullptr);
+    PTR = new Data(Traits::empty_vtx_handle(), Traits::empty_he_handle(), nullptr);
   }
 
   /*! Constructor given Vertex & Halfedge handles. */
   Td_active_vertex(Vertex_const_handle v, Halfedge_const_handle cw_he,
                    Dag_node* node = 0)
 
-  { PTR.p = new Data(v, cw_he, node); }
+  { PTR = new Data(v, cw_he, node); }
 
 
   /*! Copy constructor. */
@@ -228,7 +228,7 @@ public:
   inline const Self& self() const { return *this; }
 
   /*! Access the trapezoid id (PTR). */
-  inline unsigned long id() const { return (unsigned long) PTR.p; }
+  inline unsigned long id() const { return (unsigned long) PTR; }
 
   inline Vertex_const_handle vertex() const { return ptr()->v; }
 
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag.h
index e5eee91e724..f8a47536c85 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag.h
@@ -41,14 +41,14 @@ public: //iddo (for CC-7.2) maybe protected?
   typedef const T & const_reference;
 
 protected:
-  void init() { PTR.p = 0; }
+  void init() { PTR = 0; }
 
 public:
   Td_dag_base() {init();}
   Td_dag_base(const Td_dag_base<T> & x) : Handle(x) {}
   Td_dag_base & operator=(const Td_dag_base<T> & x)
   {Handle::operator=(x); return *this; }
-  bool operator!() const { return PTR.p == 0; }
+  bool operator!() const { return PTR == 0; }
 };
 
 template<class T>
@@ -96,9 +96,9 @@ public:
   Td_dag(){}
   Td_dag(const Td_dag_handle& dag):Td_dag_handle(dag){}
   Td_dag(const Self& dag):Td_dag_handle(dag){}
-  Td_dag(const T& rootValue){PTR.p = new node(rootValue);}
+  Td_dag(const T& rootValue){PTR = new node(rootValue);}
   Td_dag(const T& rootValue, const Self& left, const Self& right)
-  {PTR.p = new node(rootValue, left, right); rebalance_depth();}
+  {PTR = new node(rootValue, left, right); rebalance_depth();}
   ~Td_dag(){}
 
   /* --------information retrieval -------*/
@@ -145,7 +145,7 @@ public:
   }
   bool operator==(const Self& b) const
   {
-    return PTR.p==b.PTR.p;
+    return PTR==b.PTR;
   }
   bool operator!=(const Self& b) const
   {
@@ -189,7 +189,7 @@ public:
         // detach left son,redirect to dummy
         set_left(dummy);
         // set left son pointer to 0
-        ptr()->leftPtr.PTR.p=0;
+        ptr()->leftPtr.PTR=0;
         // delete dummy Td_dag
         delete dummy.ptr();
       }
@@ -204,7 +204,7 @@ public:
                                 // detach right son,redirect to dummy
         set_right(dummy);
                                 // set right son pointer to 0
-        ptr()->rightPtr.PTR.p=0;
+        ptr()->rightPtr.PTR=0;
                                 // delete dummy Td_dag
         delete dummy.ptr();
       }
@@ -371,7 +371,7 @@ protected:
   }
 #endif
  private:
-  node* ptr() const {return (node*)PTR.p;}
+  node* ptr() const {return (node*)PTR;}
 };
 
 template<class T,class Traits>
@@ -441,7 +441,7 @@ template<class T> std::ostream& operator<<(std::ostream&  out,
    tech notes:
    The code is Handle designed.
    left(),right() are designed to cope with Handle(Handle& x)
-     precondition x.PTR.p!=0
+     precondition x.PTR!=0
    operator=() performs shallow copy
    operator*() returns data type
    output is done as a binary tree.
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag_node.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag_node.h
index bbf45831519..ec4a961d8f1 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag_node.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_dag_node.h
@@ -39,7 +39,7 @@ template<class Traits>
 class Td_dag_node_base : public Handle
 {
 protected:
-  void init() { PTR.p = 0; } //MICHAL: I think it is not used - so need to be removed
+  void init() { PTR = 0; } //MICHAL: I think it is not used - so need to be removed
 
 public:
   //c'tors
@@ -57,12 +57,12 @@ public:
     return *this;
   }
 
-  //bool operator!() const {  return PTR.p == 0;  } //MICHAL: maybe use ptr(), and also can change to is_null or something similar
-  bool is_null() const { return PTR.p == 0; }
-  Rep * ptr() const { return (Rep*) PTR.p; }
+  //bool operator!() const {  return PTR == 0;  } //MICHAL: maybe use ptr(), and also can change to is_null or something similar
+  bool is_null() const { return PTR == 0; }
+  Rep * ptr() const { return (Rep*) PTR; }
 protected:
-  //Rep *& ptr() { return (Rep*) PTR.p; }
-  void set_ptr(Rep* rep) { PTR.p = rep; }
+  //Rep *& ptr() { return (Rep*) PTR; }
+  void set_ptr(Rep* rep) { PTR = rep; }
 
 };
 
@@ -94,7 +94,7 @@ public:
 #ifndef CGAL_CFG_USING_BASE_MEMBER_BUG_2
 
 public:
-  //using Td_dag_node_handle::PTR.p;
+  //using Td_dag_node_handle::PTR;
   //using Td_dag_node_handle::operator!;
 
 #endif //CGAL_CFG_USING_BASE_MEMBER_BUG_2
@@ -549,7 +549,7 @@ protected:
 
 private:
 
-  Node* node() const {   return (Node*)Base::PTR.p;  }
+  Node* node() const {   return (Node*)Base::PTR;  }
 
 };
 
@@ -629,7 +629,7 @@ std::ostream& operator<< (std::ostream&  out,
    tech notes:
    The code is Handle designed.
    left_child(),right_child() are designed to cope with Handle(Handle& x)
-     precondition x.PTR.p!=0
+     precondition x.PTR!=0
    operator=() performs shallow copy
    operator*() returns data type
    output is done as a binary tree.
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_edge.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_edge.h
index 0d85f93f148..bb57f7c6d1c 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_edge.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_edge.h
@@ -128,7 +128,7 @@ public:
 
  private:
 
-  Data* ptr() const { return (Data*)(PTR.p);  }
+  Data* ptr() const { return (Data*)(PTR);  }
 
 
 #ifndef CGAL_TD_DEBUG
@@ -161,7 +161,7 @@ public:
   /*! Constructor given Vertex & Halfedge handles. */
   Td_inactive_edge (boost::shared_ptr<X_monotone_curve_2>& cv, Dag_node* node = nullptr)
   {
-    PTR.p = new Data(cv,node);
+    PTR = new Data(cv,node);
   }
 
   /*! Copy constructor. */
@@ -215,7 +215,7 @@ public:
   /*! Access the trapezoid id (PTR). */
   inline unsigned long id() const
   {
-    return (unsigned long) PTR.p;
+    return (unsigned long) PTR;
   }
 
   inline X_monotone_curve_2& curve() const
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_fictitious_vertex.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_fictitious_vertex.h
index cf2d75d79ec..03ca8d563c7 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_fictitious_vertex.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_fictitious_vertex.h
@@ -133,7 +133,7 @@ public:
 
  private:
 
-  Data* ptr() const { return (Data*)(PTR.p);  }
+  Data* ptr() const { return (Data*)(PTR);  }
 
         Curve_end vtx_to_ce(Vertex_const_handle v) const
   {
@@ -185,7 +185,7 @@ public:
   {
     Curve_end v_ce(vtx_to_ce(v_before_rem));
 
-    PTR.p = new Data( v_ce.cv(), v_ce.ce(), node);
+    PTR = new Data( v_ce.cv(), v_ce.ce(), node);
 
   }
 
@@ -241,7 +241,7 @@ public:
   /*! Access the trapezoid id (PTR). */
   inline unsigned long id() const
   {
-    return (unsigned long) PTR.p;
+    return (unsigned long) PTR;
   }
 
 
diff --git a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_vertex.h b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_vertex.h
index 0c42b1e7669..409a6f576ee 100644
--- a/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_vertex.h
+++ b/Arrangement_on_surface_2/include/CGAL/Arr_point_location/Td_inactive_vertex.h
@@ -127,7 +127,7 @@ public:
 
  private:
 
-  Data* ptr() const { return (Data*)(PTR.p);  }
+  Data* ptr() const { return (Data*)(PTR);  }
 
 
 #ifndef CGAL_TD_DEBUG
@@ -162,7 +162,7 @@ public:
   /*! Constructor given Vertex & Halfedge handles. */
   Td_inactive_vertex (Vertex_const_handle v_before_rem, Dag_node* node = nullptr)
   {
-    PTR.p = new Data(v_before_rem->point(), node);
+    PTR = new Data(v_before_rem->point(), node);
   }
 
 
@@ -217,7 +217,7 @@ public:
   /*! Access the trapezoid id (PTR). */
   inline unsigned long id() const
   {
-    return (unsigned long) PTR.p;
+    return (unsigned long) PTR;
   }
 
   inline Point& point() const
diff --git a/BGL/include/CGAL/boost/graph/parameters_interface.h b/BGL/include/CGAL/boost/graph/parameters_interface.h
index aa6845ab917..75acf6a7b0d 100644
--- a/BGL/include/CGAL/boost/graph/parameters_interface.h
+++ b/BGL/include/CGAL/boost/graph/parameters_interface.h
@@ -178,6 +178,12 @@ CGAL_add_named_parameter(with_dihedral_angle_t, with_dihedral_angle, with_dihedr
 CGAL_add_named_parameter(optimize_anchor_location_t, optimize_anchor_location, optimize_anchor_location)
 CGAL_add_named_parameter(pca_plane_t, pca_plane, pca_plane)
 
+// tetrahedral remeshing parameters
+CGAL_add_named_parameter(remesh_boundaries_t, remesh_boundaries, remesh_boundaries)
+CGAL_add_named_parameter(cell_selector_t, cell_selector, cell_selector)
+CGAL_add_named_parameter(facet_is_constrained_t, facet_is_constrained, facet_is_constrained_map)
+CGAL_add_named_parameter(remeshing_visitor_t, remeshing_visitor, remeshing_visitor)
+
 // output parameters
 CGAL_add_named_parameter(face_proxy_map_t, face_proxy_map, face_proxy_map)
 CGAL_add_named_parameter(proxies_t, proxies, proxies)
diff --git a/Boolean_set_operations_2/include/CGAL/Boolean_set_operations_2/Polygon_2_curve_iterator.h b/Boolean_set_operations_2/include/CGAL/Boolean_set_operations_2/Polygon_2_curve_iterator.h
index 39a5e7dd34a..833f9afd571 100644
--- a/Boolean_set_operations_2/include/CGAL/Boolean_set_operations_2/Polygon_2_curve_iterator.h
+++ b/Boolean_set_operations_2/include/CGAL/Boolean_set_operations_2/Polygon_2_curve_iterator.h
@@ -60,9 +60,9 @@ public:
     Edge_const_iterator m_curr_edge;   // points to the current edge iterator
 
 public:
-    Polygon_2_curve_iterator< X_monotone_curve_2_, Polygon_ >(){}
+    Polygon_2_curve_iterator(){}
 
-    Polygon_2_curve_iterator< X_monotone_curve_2_, Polygon_ >
+    Polygon_2_curve_iterator
       (const Polygon* pgn, Edge_const_iterator ci) : m_pgn(pgn),
                                                      m_curr_edge(ci) {}
 
diff --git a/Boolean_set_operations_2/include/CGAL/Gps_circle_segment_traits_2.h b/Boolean_set_operations_2/include/CGAL/Gps_circle_segment_traits_2.h
index 1d29214e267..4b88536cf14 100644
--- a/Boolean_set_operations_2/include/CGAL/Gps_circle_segment_traits_2.h
+++ b/Boolean_set_operations_2/include/CGAL/Gps_circle_segment_traits_2.h
@@ -27,7 +27,7 @@ class Gps_circle_segment_traits_2 :
   public Gps_traits_2<Arr_circle_segment_traits_2<Kernel_, Filer_> >
 {
 public:
-  Gps_circle_segment_traits_2<Kernel_, Filer_>(bool use_cache = false) :
+  Gps_circle_segment_traits_2(bool use_cache = false) :
     Gps_traits_2<Arr_circle_segment_traits_2<Kernel_, Filer_> >()
   {
     this->m_use_cache = use_cache;
diff --git a/Bounding_volumes/examples/Approximate_min_ellipsoid_d/CMakeLists.txt b/Bounding_volumes/examples/Approximate_min_ellipsoid_d/CMakeLists.txt
index 5ea12f55be3..9c066bd6cf4 100644
--- a/Bounding_volumes/examples/Approximate_min_ellipsoid_d/CMakeLists.txt
+++ b/Bounding_volumes/examples/Approximate_min_ellipsoid_d/CMakeLists.txt
@@ -8,15 +8,18 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0 QUIET) #(3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
   # create a target per cppfile
   file(GLOB cppfiles RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/*.cpp)
   foreach(cppfile ${cppfiles})
-    if(NOT (${cppfile} STREQUAL "ellipsoid.cpp") OR EIGEN3_FOUND)
-      create_single_source_cgal_program( "${cppfile}" )
-      if (EIGEN3_FOUND)
-        get_filename_component(target ${cppfile} NAME_WE)
-        CGAL_target_use_Eigen(${target})
+    if(NOT (${cppfile} STREQUAL "ellipsoid.cpp") OR TARGET CGAL::Eigen_support)
+      get_filename_component(target ${cppfile} NAME_WE)
+      add_executable(${target} ${cppfile})
+      if (TARGET CGAL::Eigen_support)
+        target_link_libraries(${target} CGAL::CGAL CGAL::Eigen_support)
+      else()
+        target_link_libraries(${target} CGAL::CGAL)
       endif()
     endif()
   endforeach()
@@ -26,4 +29,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Bounding_volumes/test/Bounding_volumes/CMakeLists.txt b/Bounding_volumes/test/Bounding_volumes/CMakeLists.txt
index 804517aea26..5a29e19f887 100644
--- a/Bounding_volumes/test/Bounding_volumes/CMakeLists.txt
+++ b/Bounding_volumes/test/Bounding_volumes/CMakeLists.txt
@@ -14,15 +14,18 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0 QUIET) #(3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
   # create a target per cppfile
   file(GLOB cppfiles RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/*.cpp)
   foreach(cppfile ${cppfiles})
-    if(NOT (${cppfile} STREQUAL "Approximate_min_ellipsoid_d.cpp") OR EIGEN3_FOUND)
-      create_single_source_cgal_program( "${cppfile}" )
-      if (EIGEN3_FOUND)
-        get_filename_component(target ${cppfile} NAME_WE)
-        CGAL_target_use_Eigen(${target})
+    if(NOT (${cppfile} STREQUAL "Approximate_min_ellipsoid_d.cpp") OR TARGET CGAL::Eigen_support)
+      get_filename_component(target ${cppfile} NAME_WE)
+      add_executable(${target} ${cppfile})
+      if (TARGET CGAL::Eigen_support)
+        target_link_libraries(${target} CGAL::CGAL CGAL::Eigen_support)
+      else()
+        target_link_libraries(${target} CGAL::CGAL)
       endif()
     endif()
   endforeach()
@@ -32,4 +35,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Box_intersection_d/test/Box_intersection_d/CMakeLists.txt b/Box_intersection_d/test/Box_intersection_d/CMakeLists.txt
index 6f4ec1704ce..de7955c4208 100644
--- a/Box_intersection_d/test/Box_intersection_d/CMakeLists.txt
+++ b/Box_intersection_d/test/Box_intersection_d/CMakeLists.txt
@@ -8,6 +8,7 @@ project( Box_intersection_d_Tests )
 find_package( CGAL QUIET )
 
 find_package( TBB )
+include(CGAL_TBB_support)
 
 if ( CGAL_FOUND )
 
@@ -16,12 +17,11 @@ if ( CGAL_FOUND )
   create_single_source_cgal_program( "random_set_test.cpp" )
   create_single_source_cgal_program( "test_box_grid.cpp" )
 
-  if( TBB_FOUND )
-    CGAL_target_use_TBB( test_box_grid )
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(test_box_grid PUBLIC CGAL::TBB_support)
   else()
     message( STATUS "NOTICE: Intel TBB was not found. Sequential code will be used." )
   endif()
 else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 endif()
-
diff --git a/CGAL_ipelets/demo/CGAL_ipelets/CMakeLists.txt b/CGAL_ipelets/demo/CGAL_ipelets/CMakeLists.txt
index 18e2f342352..6e6749d8619 100644
--- a/CGAL_ipelets/demo/CGAL_ipelets/CMakeLists.txt
+++ b/CGAL_ipelets/demo/CGAL_ipelets/CMakeLists.txt
@@ -27,7 +27,8 @@ if ( CGAL_FOUND )
   include(${CGAL_USE_FILE})
 
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (NOT EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (NOT TARGET CGAL::Eigen_support)
     message(STATUS "NOTICE: This project requires the Eigen library, and will not be compiled.")
     return()
   endif()
@@ -140,8 +141,7 @@ if ( CGAL_FOUND )
     foreach(IPELET ${CGAL_IPELETS})
       add_library(CGAL_${IPELET} MODULE ${IPELET}.cpp)
       add_to_cached_list(CGAL_EXECUTABLE_TARGETS CGAL_${IPELET})
-      target_link_libraries(CGAL_${IPELET} PRIVATE CGAL::CGAL ${IPE_LIBRARIES})
-      CGAL_target_use_Eigen(CGAL_${IPELET})
+      target_link_libraries(CGAL_${IPELET} PRIVATE CGAL::CGAL CGAL::Eigen_support ${IPE_LIBRARIES})
       if ( IPELET_INSTALL_DIR )
         install(TARGETS CGAL_${IPELET} DESTINATION ${IPELET_INSTALL_DIR})
         if (WITH_IPE_7)
@@ -151,14 +151,12 @@ if ( CGAL_FOUND )
       cgal_add_compilation_test(CGAL_${IPELET})
     endforeach(IPELET)
     if(CGAL_Core_FOUND)
-      target_link_libraries(CGAL_cone_spanners PRIVATE CGAL::CGAL_Core)
-      CGAL_target_use_Eigen(CGAL_cone_spanners)
+      target_link_libraries(CGAL_cone_spanners PRIVATE CGAL::CGAL_Core CGAL::Eigen_support)
     endif()
     #example in doc not installed
     add_library(simple_triangulation MODULE simple_triangulation.cpp)
     add_to_cached_list(CGAL_EXECUTABLE_TARGETS simple_triangulation)
-    target_link_libraries(simple_triangulation ${IPE_LIBRARIES})
-    CGAL_target_use_Eigen(simple_triangulation)
+    target_link_libraries(simple_triangulation CGAL::Eigen_support ${IPE_LIBRARIES})
     cgal_add_compilation_test(simple_triangulation)
 
   else()
diff --git a/Classification/examples/Classification/CMakeLists.txt b/Classification/examples/Classification/CMakeLists.txt
index d0f9f8c55a2..55211fcf0e3 100644
--- a/Classification/examples/Classification/CMakeLists.txt
+++ b/Classification/examples/Classification/CMakeLists.txt
@@ -24,32 +24,39 @@ endif()
 set(Classification_dependencies_met TRUE)
 
 find_package( Boost OPTIONAL_COMPONENTS serialization iostreams )
-if (NOT Boost_SERIALIZATION_FOUND)
+include(CGAL_Boost_serialization_support)
+include(CGAL_Boost_iostreams_support)
+
+if (NOT TARGET CGAL::Boost_serialization_support)
   message(STATUS "NOTICE: This project requires Boost Serialization, and will not be compiled.")
   set(Classification_dependencies_met FALSE)
 endif()
-if (NOT Boost_IOSTREAMS_FOUND)
+if (NOT TARGET CGAL::Boost_iostreams_support)
   message(STATUS "NOTICE: This project requires Boost IO Streams, and will not be compiled.")
   set(Classification_dependencies_met FALSE)
 endif()
 
 find_package(OpenCV QUIET COMPONENTS core ml) # Need core + machine learning
-if (NOT OpenCV_FOUND)
+include(CGAL_OpenCV_support)
+if (NOT TARGET CGAL::OpenCV_support)
   message(STATUS "NOTICE: OpenCV was not found. OpenCV random forest predicate for classification won't be available.")
 endif()
 
 find_package(TensorFlow QUIET)
-if (NOT TensorFlow_FOUND)
+include(CGAL_TensorFlow_support)
+if (NOT TARGET CGAL::TensorFlow_support)
   message(STATUS "NOTICE: TensorFlow was not found. TensorFlow neural network predicate for classification won't be available.")
 endif()
 
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   set(Classification_dependencies_met FALSE)
 endif()
 
 find_package(TBB QUIET)
+include(CGAL_TBB_support)
 
 if (NOT Classification_dependencies_met)
   return()
@@ -63,14 +70,14 @@ create_single_source_cgal_program( "example_mesh_classification.cpp" )
 create_single_source_cgal_program( "example_cluster_classification.cpp" )
 create_single_source_cgal_program( "gis_tutorial_example.cpp" )
 
-if (OpenCV_FOUND)
+if (TARGET CGAL::OpenCV_support)
   create_single_source_cgal_program( "example_opencv_random_forest.cpp" )
-  CGAL_target_use_OpenCV(example_opencv_random_forest)
+  target_link_libraries(example_opencv_random_forest PUBLIC CGAL::OpenCV_support)
 endif()
 
-if (TensorFlow_FOUND)
+if (TARGET CGAL::TensorFlow_support)
   create_single_source_cgal_program( "example_tensorflow_neural_network.cpp" )
-  CGAL_target_use_TensorFlow(example_tensorflow_neural_network)
+  target_link_libraries(example_opencv_random_forest PUBLIC CGAL::TensorFlow_support)
 endif()
 
 foreach(target
@@ -84,11 +91,12 @@ foreach(target
     example_tensorflow_neural_network
     gis_tutorial_example)
   if(TARGET ${target})
-    CGAL_target_use_Eigen(${target})
-    CGAL_target_use_Boost_IOStreams(${target})
-    CGAL_target_use_Boost_Serialization(${target})
-    if(TBB_FOUND)
-      CGAL_target_use_TBB(${target})
+    target_link_libraries(${target} PUBLIC
+      CGAL::Eigen_support
+      CGAL::Boost_iostreams_support
+      CGAL::Boost_serialization_support)
+    if(TARGET CGAL::TBB_support)
+      target_link_libraries(${target} PUBLIC CGAL::TBB_support)
     endif()
   endif()
 endforeach()
diff --git a/Classification/test/Classification/CMakeLists.txt b/Classification/test/Classification/CMakeLists.txt
index 9dc6193801a..e9ad1a332dc 100644
--- a/Classification/test/Classification/CMakeLists.txt
+++ b/Classification/test/Classification/CMakeLists.txt
@@ -24,22 +24,27 @@ endif()
 set(Classification_dependencies_met TRUE)
 
 find_package( Boost OPTIONAL_COMPONENTS serialization iostreams )
-if (NOT Boost_SERIALIZATION_FOUND)
+include(CGAL_Boost_serialization_support)
+include(CGAL_Boost_iostreams_support)
+
+if (NOT TARGET CGAL::Boost_serialization_support)
   message(STATUS "NOTICE: This project requires Boost Serialization, and will not be compiled.")
   set(Classification_dependencies_met FALSE)
 endif()
-if (NOT Boost_IOSTREAMS_FOUND)
+if (NOT TARGET CGAL::Boost_iostreams_support)
   message(STATUS "NOTICE: This project requires Boost IO Streams, and will not be compiled.")
   set(Classification_dependencies_met FALSE)
 endif()
 
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   set(Classification_dependencies_met FALSE)
 endif()
 
 find_package(TBB QUIET)
+include(CGAL_TBB_support)
 
 if (NOT Classification_dependencies_met)
   return()
@@ -49,11 +54,11 @@ create_single_source_cgal_program( "test_classification_point_set.cpp" )
 create_single_source_cgal_program( "test_classification_io.cpp" )
 
 foreach(target test_classification_point_set test_classification_io)
-  CGAL_target_use_Eigen(${target})
-  CGAL_target_use_Boost_IOStreams(${target})
-  CGAL_target_use_Boost_Serialization(${target})
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(${target})
+  target_link_libraries(${target} PUBLIC
+    CGAL::Eigen_support
+    CGAL::Boost_iostreams_support
+    CGAL::Boost_serialization_support)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(${target} PUBLIC CGAL::TBB_support)
   endif()
 endforeach()
-
diff --git a/Combinatorial_map/include/CGAL/Cell_attribute.h b/Combinatorial_map/include/CGAL/Cell_attribute.h
index 2154b9d1ffd..8fa4def7b3c 100644
--- a/Combinatorial_map/include/CGAL/Cell_attribute.h
+++ b/Combinatorial_map/include/CGAL/Cell_attribute.h
@@ -197,8 +197,8 @@ namespace CGAL {
 
     void * for_compact_container() const
     { return vp; }
-    void * & for_compact_container()
-    { return vp; }
+    void for_compact_container(void *p)
+    { vp = p; }
 
   private:
     /// Reference counting: the number of darts linked to this cell.
@@ -310,8 +310,8 @@ namespace CGAL {
 
     void * for_compact_container() const
     { return mdart.for_compact_container(); }
-    void * & for_compact_container()
-    { return mdart.for_compact_container(); }
+    void for_compact_container(void *p)
+    { mdart.for_compact_container(p); }
 
   private:
     /// The dart handle associated with the cell.
diff --git a/Combinatorial_map/include/CGAL/Dart.h b/Combinatorial_map/include/CGAL/Dart.h
index eab9f898131..bfc21e7b25a 100644
--- a/Combinatorial_map/include/CGAL/Dart.h
+++ b/Combinatorial_map/include/CGAL/Dart.h
@@ -105,8 +105,8 @@ namespace CGAL {
 
     void * for_compact_container() const
     { return mf[0].for_compact_container(); }
-    void * & for_compact_container()
-    { return mf[0].for_compact_container(); }
+    void for_compact_container(void *p)
+    { mf[0].for_compact_container(p); }
 
     Dart_handle get_f(unsigned int i) const
     {
diff --git a/Convex_hull_2/include/CGAL/IO/Tee_for_output_iterator.h b/Convex_hull_2/include/CGAL/IO/Tee_for_output_iterator.h
index 3a298f6b6c0..26aee3bba75 100644
--- a/Convex_hull_2/include/CGAL/IO/Tee_for_output_iterator.h
+++ b/Convex_hull_2/include/CGAL/IO/Tee_for_output_iterator.h
@@ -39,7 +39,7 @@ class Tee_for_output_iterator
 
 public:
   Tee_for_output_iterator(const OutputIterator& o) : o_it(o)
-  {  PTR.p = (Rep*) new _Tee_for_output_iterator_rep<T>(); }
+  {  PTR = (Rep*) new _Tee_for_output_iterator_rep<T>(); }
 
   Tee_for_output_iterator<OutputIterator,T>&
   operator=(const T& value)
@@ -82,7 +82,7 @@ public:
 
   _Tee_for_output_iterator_rep<T>*
   ptr()
-  { return (_Tee_for_output_iterator_rep<T>*)(PTR.p); }
+  { return (_Tee_for_output_iterator_rep<T>*)PTR; }
 
 protected:
   OutputIterator o_it;
diff --git a/Convex_hull_d/include/CGAL/Regular_complex_d.h b/Convex_hull_d/include/CGAL/Regular_complex_d.h
index 753637ec1e5..4a5a32b1213 100644
--- a/Convex_hull_d/include/CGAL/Regular_complex_d.h
+++ b/Convex_hull_d/include/CGAL/Regular_complex_d.h
@@ -87,7 +87,7 @@ public:
 
   void* pp;
   void*   for_compact_container() const { return pp; }
-  void* & for_compact_container()       { return pp; }
+  void for_compact_container(void *p) { pp = p; }
 
 #ifdef CGAL_USE_LEDA
   LEDA_MEMORY(RC_vertex_d)
@@ -153,7 +153,7 @@ public:
 
   void* pp;
   void*   for_compact_container() const { return pp; }
-  void* & for_compact_container()       { return pp; }
+  void for_compact_container(void *p) { pp = p; }
 
   #if 0
   struct Point_const_iterator {
diff --git a/Documentation/doc/Documentation/Developer_manual/create_and_use_a_cmakelist.txt b/Documentation/doc/Documentation/Developer_manual/create_and_use_a_cmakelist.txt
index afc413a7dd7..0fffe791b9b 100644
--- a/Documentation/doc/Documentation/Developer_manual/create_and_use_a_cmakelist.txt
+++ b/Documentation/doc/Documentation/Developer_manual/create_and_use_a_cmakelist.txt
@@ -18,7 +18,7 @@ find_package(CGAL REQUIRED COMPONENTS Core)
 target_link_libraries(my_executable CGAL::CGAL CGAL::CGAL_Core)
 \endcode
 
-There are also some cmake macros to link with \cgal dependencies that can be found in
+There are also imported targets to link with \cgal dependencies that can be found in
 the section \subpage thirdparty.
 
 \note The \cgal targets define the following compiler flags:
diff --git a/Documentation/doc/Documentation/Third_party.txt b/Documentation/doc/Documentation/Third_party.txt
index 71e3c43d291..ea4987e97e5 100644
--- a/Documentation/doc/Documentation/Third_party.txt
+++ b/Documentation/doc/Documentation/Third_party.txt
@@ -132,8 +132,8 @@ sparse linear solvers and singular value decompositions.  A package
 dependency over \sc{Eigen} is marked on the <a
 href="https://doc.cgal.org/latest/Manual/packages.html">Package
 Overview</a> page. In order to use Eigen in \cgal programs, the
-provided CMake function `CGAL_target_use_Eigen(<target>)` should be
-used.
+executables should be linked with the CMake imported target
+`CGAL::Eigen_support` provided in `CGAL_Eigen_support.cmake`.
 
 The \sc{Eigen} web site is <A HREF="http://eigen.tuxfamily.org/index.php?title=Main_Page">`http://eigen.tuxfamily.org`</A>.
 
@@ -142,8 +142,7 @@ The \sc{Eigen} web site is <A HREF="http://eigen.tuxfamily.org/index.php?title=M
 \sc{OpenGR} is a set C++ libraries for 3D Global Registration released under the terms of the APACHE V2 licence.
 
 \cgal provides wrappers for the Super4PCS algorithm of \sc{OpenGR} in the \ref PkgPointSetProcessing3Ref
-packages. In order to use \sc{OpenGR} in \cgal programs, the provided CMake function
-`CGAL_target_use_OpenGR(<target>)` should be used.
+packages. In order to use \sc{OpenGR} in \cgal programs, the executables should be linked with the CMake imported target `CGAL::OpenGR_support` provided in `CGAL_OpenGR_support.cmake`.
 
 The \sc{OpenGR} web site is <A HREF="https://github.com/STORM-IRIT/OpenGR">`https://github.com/STORM-IRIT/OpenGR`</A>.
 
@@ -152,8 +151,10 @@ The \sc{OpenGR} web site is <A HREF="https://github.com/STORM-IRIT/OpenGR">`http
 \sc{libpointmatcher} is a modular library implementing the Iterative Closest Point (ICP) algorithm for aligning point clouds, released under a permissive BSD license.
 
 \cgal provides wrappers for the ICP algorithm of \sc{libpointmatcher} in the \ref PkgPointSetProcessing3Ref
-packages. In order to use \sc{libpointmatcher} in \cgal programs, the provided CMake function
-`CGAL_target_use_pointmatcher(<target>)` should be used.
+packages. In order to use \sc{libpointmatcher} in \cgal programs, the
+executables should be linked with the CMake imported target
+`CGAL::pointmatcher_support` provided in
+`CGAL_pointmatcher_support.cmake`.
 
 The \sc{libpointmatcher} web site is <A
 HREF="https://github.com/ethz-asl/libpointmatcher">`https://github.com/ethz-asl/libpointmatcher`</A>.
@@ -220,8 +221,9 @@ It can be downloaded from <A HREF="http://esbtl.sourceforge.net/">`http://esbtl.
 programs that take advantage of multi-core processors.
 
 In \cgal, \sc{Tbb} is used by the packages that offer parallel
-code. In order to use \sc{Tbb} in \cgal programs, the provided CMake
-function `CGAL_target_use_TBB(<target>)` should be used.
+code. In order to use \sc{Tbb} in \cgal programs, the executables
+should be linked with the CMake imported target `CGAL::TBB_support`
+provided in `CGAL_TBB_support.cmake`.
 
 The \sc{Tbb} web site is <A HREF="https://www.threadingbuildingblocks.org">`https://www.threadingbuildingblocks.org`</A>.
 
@@ -231,9 +233,10 @@ The \sc{Tbb} web site is <A HREF="https://www.threadingbuildingblocks.org">`http
 the LAS format (or the compressed LAZ format).
 
 In \cgal, \sc{LASlib} is used to provide input and output functions in
-the \ref PkgPointSetProcessing3 package. In order to use \sc{LASlib} in
-\cgal programs, the provided CMake function
-`CGAL_target_use_LASLIB(<target>)` should be used.
+the \ref PkgPointSetProcessing3 package. In order to use \sc{LASlib}
+in \cgal programs, the executables should be linked with the CMake
+imported target `CGAL::LASLIB_support` provided in
+`CGAL_LASLIB_support.cmake`.
 
 The \sc{LASlib} web site is <a
 href="https://rapidlasso.com/lastools/">`https://rapidlasso.com/lastools/`</a>. \sc{LASlib}
@@ -247,8 +250,9 @@ CMake based install procedure</a>.
 vision, computer graphics and machine learning.
 
 In \cgal, \sc{OpenCV} is used by the \ref PkgClassification
-package. In order to use \sc{OpenCV} in \cgal programs, the provided
-CMake function `CGAL_target_use_OpenCV(<target>)` should be used.
+package. In order to use \sc{OpenCV} in \cgal programs, the
+executables should be linked with the CMake imported target
+`CGAL::OpenCV_support` provided in `CGAL_OpenCV_support.cmake`.
 
 The \sc{OpenCV} web site is <A HREF="https://opencv.org/">`https://opencv.org/`</A>.
 
@@ -266,8 +270,10 @@ enable and compile the following targets:
 - `tensorflow_BUILD_PYTHON_BINDINGS`
 - `tensorflow_BUILD_SHARED_LIB`.
 
-In order to use \sc{TensorFlow} in \cgal programs, the provided CMake
-function `CGAL_target_use_TensorFlow(<target>)` should be used.
+In order to use \sc{TensorFlow} in \cgal programs, the executables
+should be linked with the CMake imported target
+`CGAL::TensorFlow_support` provided in
+`CGAL_TensorFlow_support.cmake`.
 
 The \sc{TensorFlow} web site is <A HREF="https://www.tensorflow.org/">`https://www.tensorflow.org/`</A>.
 
@@ -310,8 +316,9 @@ for more information.
 
 In \cgal, \sc{GLPK} provides an optional linear integer program solver
 in the \ref PkgPolygonalSurfaceReconstruction package. In order to use
-\sc{GLPK} in \cgal programs, the provided CMake function
-`CGAL_target_use_GLPK(<target>)` should be used.
+\sc{GLPK} in \cgal programs, the executables should be linked with the
+CMake imported target `CGAL::GLPK_support` provided in
+`CGAL_GLPK_support.cmake`.
 
 The \sc{GLPK} web site is <A HREF="https://www.gnu.org/software/glpk/">`https://www.gnu.org/software/glpk/`</A>.
 
@@ -321,8 +328,9 @@ The \sc{GLPK} web site is <A HREF="https://www.gnu.org/software/glpk/">`https://
 
 In \cgal, \sc{SCIP} provides an optional linear integer program solver
 in the \ref PkgPolygonalSurfaceReconstruction package. In order to use
-\sc{SCIP} in \cgal programs, the provided CMake function
-`CGAL_target_use_SCIP(<target>)` should be used.
+\sc{SCIP} in \cgal programs, the executables should be linked with the
+CMake imported target `CGAL::SCIP_support` provided in
+`CGAL_SCIP_support.cmake`.
 
 The \sc{SCIP} web site is <A HREF="http://scip.zib.de/">`http://scip.zib.de/`</A>.
 
diff --git a/Documentation/doc/Documentation/Usage.txt b/Documentation/doc/Documentation/Usage.txt
index 38d2b257697..247348cab68 100644
--- a/Documentation/doc/Documentation/Usage.txt
+++ b/Documentation/doc/Documentation/Usage.txt
@@ -60,12 +60,6 @@ On most operating systems, package managers offer \cgal and its essential third
 On macOS, we recommend using of <a href="https://brew.sh/">Homebrew</a> in the following way:
 
     brew install cgal
-    brew install cgal-qt5   #(only for GUI)
-
-You should check that cgal and cgal-qt5 are correctly "linked", especially when upgrading from an old version. If not, run the following command:
-
-    brew link cgal
-    brew link cgal-qt5  #(if you installed it)
 
 On Linux distributions such as `Debian`/`Ubuntu`/`Mint`, use `apt-get` in the following way:
 
diff --git a/Documentation/doc/Documentation/packages.txt b/Documentation/doc/Documentation/packages.txt
index 5fb6e1a5446..a18528a063d 100644
--- a/Documentation/doc/Documentation/packages.txt
+++ b/Documentation/doc/Documentation/packages.txt
@@ -90,6 +90,7 @@
 \package_listing{Surface_mesher}
 \package_listing{Skin_surface_3}
 \package_listing{Mesh_3}
+\package_listing{Tetrahedral_remeshing}
 \package_listing{Periodic_3_mesh_3}
 
 \cgalPackageSection{PartReconstruction,Shape Reconstruction}
diff --git a/Documentation/doc/biblio/cgal_manual.bib b/Documentation/doc/biblio/cgal_manual.bib
index e2a2fd57555..6dcd0e958c7 100644
--- a/Documentation/doc/biblio/cgal_manual.bib
+++ b/Documentation/doc/biblio/cgal_manual.bib
@@ -3127,6 +3127,14 @@ pages = "207--221"
   year={2012},
   organization={Wiley Online Library}
 }
+
+@article{faraj2016mvr,
+ author = {Noura Faraj and Jean-Marc Thiery and Tamy Boubekeur},
+ title = {Multi-Material Adaptive Volume Remesher},
+ journal = {Compurer and Graphics Journal (proc. Shape Modeling International 2016)},
+ year = {2016},
+} 
+
 % ----------------------------------------------------------------------------
 % END OF BIBFILE
 % ----------------------------------------------------------------------------
diff --git a/Documentation/doc/resources/1.8.13/menu_version.js b/Documentation/doc/resources/1.8.13/menu_version.js
index 36b298ee045..780aefa1246 100644
--- a/Documentation/doc/resources/1.8.13/menu_version.js
+++ b/Documentation/doc/resources/1.8.13/menu_version.js
@@ -3,10 +3,11 @@
 
   var url_re =  /(cgal\.geometryfactory\.com\/CGAL\/doc\/|doc\.cgal\.org\/)(master|latest|(\d\.\d+|\d\.\d+\.\d+))\//;
   var url_local =  /.*\/doc_output\//;
-  var current_version_local = '5.1-dev'
+  var current_version_local = '5.1-beta1'
   var all_versions = [
       'master',
       'latest',
+      '5.1-beta1',
       '5.0.2',
       '4.14.3',
       '4.13.2',
@@ -23,6 +24,15 @@
   ];
 
   function build_select(current_version) {
+    if( current_version == 'master') {
+      let top_elt = document.getElementById("top");
+
+      let first_element = top_elt.childNodes[0];
+      let new_div = document.createElement("p");
+      new_div.innerHTML = '⚠️ This documentation corresponds to the <a style="font-familly: monospace;" href="https://github.com/CGAL/cgal/tree/master">master</a> development branch of CGAL. It might diverge from the official releases.';
+      new_div.style.cssText = "background-color: #ff9800; margin: 1ex auto 1ex 1em; padding: 1ex; border-radius: 1ex; display: inline-block;"
+      let OK = top_elt.insertBefore(new_div, first_element);
+    }
     var buf = ['<select>'];
     $.each(all_versions, function(id) {
       var version = all_versions[id];
@@ -44,7 +54,7 @@
   }
 
   function patch_url(url, new_version) {
-    if(url.includes("doc.cgal.org")||url.includes("cgal.geometryfactory.com")){  
+    if(url.includes("doc.cgal.org")||url.includes("cgal.geometryfactory.com")){
       return url.replace(url_re, 'doc.cgal.org/' + new_version + '/');
     }
     else{
@@ -65,7 +75,7 @@
       var motherNode=$("#back-nav ul")[0];
       var node = document.createElement("LI");
       var spanNode = document.createElement("SPAN");
-      var titleNode =document.createTextNode("CGAL Version: "); 
+      var titleNode =document.createTextNode("CGAL Version: ");
       var textNode = document.createTextNode("x.y");
       spanNode.setAttribute("class", "version_menu");
       spanNode.appendChild(textNode);
@@ -90,4 +100,4 @@
         }
      }
   });
-})(); 
+})();
diff --git a/Documentation/doc/resources/1.8.14/menu_version.js b/Documentation/doc/resources/1.8.14/menu_version.js
index 36b298ee045..780aefa1246 100644
--- a/Documentation/doc/resources/1.8.14/menu_version.js
+++ b/Documentation/doc/resources/1.8.14/menu_version.js
@@ -3,10 +3,11 @@
 
   var url_re =  /(cgal\.geometryfactory\.com\/CGAL\/doc\/|doc\.cgal\.org\/)(master|latest|(\d\.\d+|\d\.\d+\.\d+))\//;
   var url_local =  /.*\/doc_output\//;
-  var current_version_local = '5.1-dev'
+  var current_version_local = '5.1-beta1'
   var all_versions = [
       'master',
       'latest',
+      '5.1-beta1',
       '5.0.2',
       '4.14.3',
       '4.13.2',
@@ -23,6 +24,15 @@
   ];
 
   function build_select(current_version) {
+    if( current_version == 'master') {
+      let top_elt = document.getElementById("top");
+
+      let first_element = top_elt.childNodes[0];
+      let new_div = document.createElement("p");
+      new_div.innerHTML = '⚠️ This documentation corresponds to the <a style="font-familly: monospace;" href="https://github.com/CGAL/cgal/tree/master">master</a> development branch of CGAL. It might diverge from the official releases.';
+      new_div.style.cssText = "background-color: #ff9800; margin: 1ex auto 1ex 1em; padding: 1ex; border-radius: 1ex; display: inline-block;"
+      let OK = top_elt.insertBefore(new_div, first_element);
+    }
     var buf = ['<select>'];
     $.each(all_versions, function(id) {
       var version = all_versions[id];
@@ -44,7 +54,7 @@
   }
 
   function patch_url(url, new_version) {
-    if(url.includes("doc.cgal.org")||url.includes("cgal.geometryfactory.com")){  
+    if(url.includes("doc.cgal.org")||url.includes("cgal.geometryfactory.com")){
       return url.replace(url_re, 'doc.cgal.org/' + new_version + '/');
     }
     else{
@@ -65,7 +75,7 @@
       var motherNode=$("#back-nav ul")[0];
       var node = document.createElement("LI");
       var spanNode = document.createElement("SPAN");
-      var titleNode =document.createTextNode("CGAL Version: "); 
+      var titleNode =document.createTextNode("CGAL Version: ");
       var textNode = document.createTextNode("x.y");
       spanNode.setAttribute("class", "version_menu");
       spanNode.appendChild(textNode);
@@ -90,4 +100,4 @@
         }
      }
   });
-})(); 
+})();
diff --git a/Documentation/doc/resources/1.8.4/menu_version.js b/Documentation/doc/resources/1.8.4/menu_version.js
index 36b298ee045..780aefa1246 100644
--- a/Documentation/doc/resources/1.8.4/menu_version.js
+++ b/Documentation/doc/resources/1.8.4/menu_version.js
@@ -3,10 +3,11 @@
 
   var url_re =  /(cgal\.geometryfactory\.com\/CGAL\/doc\/|doc\.cgal\.org\/)(master|latest|(\d\.\d+|\d\.\d+\.\d+))\//;
   var url_local =  /.*\/doc_output\//;
-  var current_version_local = '5.1-dev'
+  var current_version_local = '5.1-beta1'
   var all_versions = [
       'master',
       'latest',
+      '5.1-beta1',
       '5.0.2',
       '4.14.3',
       '4.13.2',
@@ -23,6 +24,15 @@
   ];
 
   function build_select(current_version) {
+    if( current_version == 'master') {
+      let top_elt = document.getElementById("top");
+
+      let first_element = top_elt.childNodes[0];
+      let new_div = document.createElement("p");
+      new_div.innerHTML = '⚠️ This documentation corresponds to the <a style="font-familly: monospace;" href="https://github.com/CGAL/cgal/tree/master">master</a> development branch of CGAL. It might diverge from the official releases.';
+      new_div.style.cssText = "background-color: #ff9800; margin: 1ex auto 1ex 1em; padding: 1ex; border-radius: 1ex; display: inline-block;"
+      let OK = top_elt.insertBefore(new_div, first_element);
+    }
     var buf = ['<select>'];
     $.each(all_versions, function(id) {
       var version = all_versions[id];
@@ -44,7 +54,7 @@
   }
 
   function patch_url(url, new_version) {
-    if(url.includes("doc.cgal.org")||url.includes("cgal.geometryfactory.com")){  
+    if(url.includes("doc.cgal.org")||url.includes("cgal.geometryfactory.com")){
       return url.replace(url_re, 'doc.cgal.org/' + new_version + '/');
     }
     else{
@@ -65,7 +75,7 @@
       var motherNode=$("#back-nav ul")[0];
       var node = document.createElement("LI");
       var spanNode = document.createElement("SPAN");
-      var titleNode =document.createTextNode("CGAL Version: "); 
+      var titleNode =document.createTextNode("CGAL Version: ");
       var textNode = document.createTextNode("x.y");
       spanNode.setAttribute("class", "version_menu");
       spanNode.appendChild(textNode);
@@ -90,4 +100,4 @@
         }
      }
   });
-})(); 
+})();
diff --git a/Filtered_kernel/include/CGAL/Lazy.h b/Filtered_kernel/include/CGAL/Lazy.h
index df94fc2de19..067fbe57463 100644
--- a/Filtered_kernel/include/CGAL/Lazy.h
+++ b/Filtered_kernel/include/CGAL/Lazy.h
@@ -718,17 +718,17 @@ public :
 
   Lazy(Self_rep *r)
   {
-    PTR.p = r;
+    PTR = r;
   }
 
   Lazy(const ET& e)
   {
-    PTR.p = new Lazy_rep_0<AT,ET,E2A>(e);
+    PTR = new Lazy_rep_0<AT,ET,E2A>(e);
   }
 
   Lazy(ET&& e)
   {
-    PTR.p = new Lazy_rep_0<AT,ET,E2A>(std::move(e));
+    PTR = new Lazy_rep_0<AT,ET,E2A>(std::move(e));
   }
 
   friend void swap(Lazy& a, Lazy& b) noexcept
@@ -768,7 +768,7 @@ public :
     return z;
   }
 
-  Self_rep * ptr() const { return (Self_rep*) PTR.p; }
+  Self_rep * ptr() const { return (Self_rep*) PTR; }
 };
 
 // The magic functor for Construct_bbox_[2,3], as there is no Lazy<Bbox>
diff --git a/Generator/examples/Generator/CMakeLists.txt b/Generator/examples/Generator/CMakeLists.txt
index c5ac751d26c..fa8efe5d09a 100644
--- a/Generator/examples/Generator/CMakeLists.txt
+++ b/Generator/examples/Generator/CMakeLists.txt
@@ -12,17 +12,18 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0 QUIET) #(3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
   # create a target per cppfile
   file(GLOB cppfiles RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/*.cpp)
   foreach(cppfile ${cppfiles})
     if(NOT (${cppfile} STREQUAL "random_points_in_tetrahedral_mesh_3.cpp")
         OR NOT (${cppfile} STREQUAL "random_points_on_tetrahedral_mesh_3.cpp")
-        OR EIGEN3_FOUND)
+        OR TARGET CGAL::Eigen_support)
       create_single_source_cgal_program( "${cppfile}" )
-      if (EIGEN3_FOUND)
+      if (TARGET CGAL::Eigen_support)
         get_filename_component(target ${cppfile} NAME_WE)
-        CGAL_target_use_Eigen(${target})
+        target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
       endif()
     endif()
   endforeach()
@@ -32,4 +33,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Generator/test/Generator/CMakeLists.txt b/Generator/test/Generator/CMakeLists.txt
index 3f24895ab6a..a757803d15c 100644
--- a/Generator/test/Generator/CMakeLists.txt
+++ b/Generator/test/Generator/CMakeLists.txt
@@ -12,15 +12,16 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0 QUIET) #(3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
   # create a target per cppfile
   file(GLOB cppfiles RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/*.cpp)
   foreach(cppfile ${cppfiles})
-    if(NOT (${cppfile} STREQUAL "generic_random_test.cpp") OR EIGEN3_FOUND)
+    if(NOT (${cppfile} STREQUAL "generic_random_test.cpp") OR TARGET CGAL::Eigen_support)
       create_single_source_cgal_program( "${cppfile}" )
-      if (EIGEN3_FOUND)
+      if (TARGET CGAL::Eigen_support)
         get_filename_component(target ${cppfile} NAME_WE)
-        CGAL_target_use_Eigen(${target})
+        target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
       endif()
     endif()
   endforeach()
@@ -30,4 +31,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/GraphicsView/demo/Polygon/CMakeLists.txt b/GraphicsView/demo/Polygon/CMakeLists.txt
index 4ef96ffcf74..a38afceeedd 100644
--- a/GraphicsView/demo/Polygon/CMakeLists.txt
+++ b/GraphicsView/demo/Polygon/CMakeLists.txt
@@ -16,7 +16,8 @@ endif()
 find_package(CGAL COMPONENTS Qt5 Core)
 
 find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "NOTICE: This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -46,12 +47,11 @@ if ( CGAL_FOUND AND CGAL_Qt5_FOUND AND Qt5_FOUND )
 
   # The executable itself.
   add_executable  ( Polygon_2 Polygon_2.cpp  ${DT_UI_FILES} ${DT_RESOURCE_FILES} ${CGAL_Qt5_RESOURCE_FILES} ${CGAL_Qt5_MOC_FILES} )
-  CGAL_target_use_Eigen(Polygon_2)
 
   add_to_cached_list( CGAL_EXECUTABLE_TARGETS Polygon_2 )
 
   target_link_libraries( Polygon_2 PRIVATE
-    CGAL::CGAL CGAL::CGAL_Qt5 Qt5::Gui )
+    CGAL::CGAL CGAL::CGAL_Qt5 CGAL::Eigen_support Qt5::Gui )
 
   include(${CGAL_MODULES_DIR}/CGAL_add_test.cmake)
   cgal_add_compilation_test(Polygon_2)
diff --git a/Heat_method_3/examples/Heat_method_3/CMakeLists.txt b/Heat_method_3/examples/Heat_method_3/CMakeLists.txt
index f9703071b81..0a29731a259 100644
--- a/Heat_method_3/examples/Heat_method_3/CMakeLists.txt
+++ b/Heat_method_3/examples/Heat_method_3/CMakeLists.txt
@@ -33,8 +33,9 @@ endif()
 
 
 find_package(Eigen3 3.3.0)
+include(CGAL_Eigen_support)
 
-if (NOT EIGEN3_FOUND)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library (3.3 or greater), and will not be compiled.")
   return()
 endif()
@@ -51,10 +52,10 @@ include_directories( BEFORE include )
 include( CGAL_CreateSingleSourceCGALProgram )
 
 create_single_source_cgal_program( "heat_method.cpp" )
-CGAL_target_use_Eigen(heat_method)
+target_link_libraries(heat_method PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "heat_method_polyhedron.cpp" )
-CGAL_target_use_Eigen(heat_method_polyhedron)
+target_link_libraries(heat_method_polyhedron PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "heat_method_surface_mesh.cpp" )
-CGAL_target_use_Eigen(heat_method_surface_mesh)
+target_link_libraries(heat_method_surface_mesh PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "heat_method_surface_mesh_direct.cpp" )
-CGAL_target_use_Eigen(heat_method_surface_mesh_direct)
+target_link_libraries(heat_method_surface_mesh_direct PUBLIC CGAL::Eigen_support)
diff --git a/Heat_method_3/test/Heat_method_3/CMakeLists.txt b/Heat_method_3/test/Heat_method_3/CMakeLists.txt
index 7876d80a53b..9a86ed7236c 100644
--- a/Heat_method_3/test/Heat_method_3/CMakeLists.txt
+++ b/Heat_method_3/test/Heat_method_3/CMakeLists.txt
@@ -33,8 +33,9 @@ endif()
 
 
 find_package(Eigen3 3.3.0)
+include(CGAL_Eigen_support)
 
-if (NOT EIGEN3_FOUND)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the  Eigen library (3.3 or greater), and will not be compiled.")
   return()
 endif()
@@ -49,8 +50,8 @@ include_directories( BEFORE include )
 include( CGAL_CreateSingleSourceCGALProgram )
 
 create_single_source_cgal_program( "heat_method_concept.cpp" )
-CGAL_target_use_Eigen(heat_method_concept)
+target_link_libraries(heat_method_concept PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "heat_method_surface_mesh_test.cpp" )
-CGAL_target_use_Eigen(heat_method_surface_mesh_test)
+target_link_libraries(heat_method_surface_mesh_test PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "heat_method_surface_mesh_direct_test.cpp" )
-CGAL_target_use_Eigen(heat_method_surface_mesh_direct_test)
+target_link_libraries(heat_method_surface_mesh_direct_test PUBLIC CGAL::Eigen_support)
diff --git a/Inscribed_areas/include/CGAL/Largest_empty_iso_rectangle_2.h b/Inscribed_areas/include/CGAL/Largest_empty_iso_rectangle_2.h
index 601f4d3e9d6..382c80e2c0b 100644
--- a/Inscribed_areas/include/CGAL/Largest_empty_iso_rectangle_2.h
+++ b/Inscribed_areas/include/CGAL/Largest_empty_iso_rectangle_2.h
@@ -233,12 +233,11 @@ public:
   ~Largest_empty_iso_rectangle_2();
 
   //! An operator=
-  Largest_empty_iso_rectangle_2<T>&
-    operator =(const Largest_empty_iso_rectangle_2<T>& ler);
+  Largest_empty_iso_rectangle_2&
+    operator =(const Largest_empty_iso_rectangle_2& ler);
 
   //! A copy constructor
-  Largest_empty_iso_rectangle_2<T>(
-               const Largest_empty_iso_rectangle_2<T>& ler);
+  Largest_empty_iso_rectangle_2(const Largest_empty_iso_rectangle_2& ler);
 
   struct Internal_point {
     Point_2 x_part;// the x coordinate of the point
diff --git a/Installation/CHANGES.md b/Installation/CHANGES.md
index 0f71f6532db..b6cc3849288 100644
--- a/Installation/CHANGES.md
+++ b/Installation/CHANGES.md
@@ -1,200 +1,252 @@
 Release History
 ===============
 
-[Release 5.1] (https://github.com/CGAL/cgal/releases/tag/releases%2FCGAL-5.1)
-
-### 3D Fast Intersection and Distance Computation
-- The introduction of the usage of the search tree by default for all distance queries
-  in the 5.0 release was actually not lazy contrary to what was announced. The behavior of the
-  search tree is now the following: it will be used except if an explicit call to `do_not_accelerate_distance_queries()`
-  is made. The construction of the search tree (once insertion of primitives is done) will be triggered by the first
-  distance query or by an explicit call to `accelerate_distance_queries()`.
-- **Breaking change**: `accelerate_distance_queries()` and `do_not_accelerate_distance_queries()` are not longer `const` functions.
-
-### Optimal Bounding Box (new package)
-- This package implements an optimization algorithm that aims to construct a close approximation
-  of the *optimal bounding box* of a mesh or a point set, which is defined as the smallest
-  (in terms of volume) bounding box that contains a given mesh or point set.
-
-### 2D and 3D Linear Geometry Kernel
- - Add `CompareSignedDistanceToLine_2` in the 2D/3D Kernel concept to compare
-   the signed distance of two points to a line, or the line passing through two given points.
-   Corresponding functors in the model (`Compare_signed_distance_to_line_2`) are also added.
-
-### Point Set Processing
- - Add a function `CGAL::cluster_point_set()` that segments a point
-   cloud into connected components based on a distance threshold.
-
-### 2D Triangulations
- - Add function `split_subconstraint_graph_into_constraints()` to
-   `Constrained_triangulation_plus_2` to initialize the constraints
-   from a soup of disconnected segments that should first be split
-   into polylines.
-
-### 3D Convex Hulls
- -   The long-deprecated function `CGAL::convex_hull_3_to_polyhedron_3()` has been removed.
-     The function `CGAL::convex_hull_3_to_face_graph()` should be used instead.
-
-### dD Spatial Searching
-
- - The kd-tree can now be built in parallel: `CGAL::Kd_tree::build()`
-   is given an optional template parameter `ConcurrencyTag` (default
-   value remains `CGAL::Sequential_tag` for backward compatibility).
-
-Release 5.0
+[Release 5.1](https://github.com/CGAL/cgal/releases/tag/releases%2FCGAL-5.1)
 -----------
 
-Release date: June 2020
+Release date: July 2020
 
-### 2D Arrangement on Surface
- -   Changed intersection return type from legacy `CGAL::Object` to modern
-     `boost::variant` in all traits concepts and models.
-     As there is an implicit conversion from `boost::variant` to `CGAL::Object`, the
+### [Tetrahedral Remeshing](https://doc.cgal.org/5.1/Manual/packages.html#PkgTetrahedralRemeshing) (new package)
+
+-   This package implements a tetrahedral isotropic remeshing algorithm,
+    that improves the quality of tetrahedra in terms of dihedral angles,
+    while targeting a given edge length.
+
+### [Surface Mesh Topology](https://doc.cgal.org/5.1/Manual/packages.html#PkgSurfaceMeshTopologySummary) (new package)
+
+-   This package enables the computation of some topological invariants of surfaces, such as:
+    - test if two (closed) curves on a combinatorial surface are homotopic. Users can choose
+      between free homotopy and homotopy with fixed endpoints;
+    - test is a curve is contractible;
+    - compute shortest non-contractible cycles on a surface, with or without weights on edges.
+
+    See also the associated [blog entry](https://www.cgal.org/2020/05/08/Surface_mesh_topology/).
+
+### [Optimal Bounding Box](https://doc.cgal.org/5.1/Manual/packages.html#PkgOptimalBoundingBox) (new package)
+
+-   This package implements an optimization algorithm that aims to construct a close approximation
+    of the *optimal bounding box* of a mesh or a point set, which is defined as the smallest
+    (in terms of volume) bounding box that contains a given mesh or point set.
+
+    See also the associated [blog entry](https://www.cgal.org/2020/04/20/Optimal_bounding_box/).
+
+### [Tutorials](https://doc.cgal.org/5.1/Manual/tutorials.html)
+
+-   Two new, detailed tutorials have been added:
+    - [Surface Reconstruction from Point Clouds](https://doc.cgal.org/5.1/Manual/tuto_reconstruction.html),
+      which goes over a typical full processing pipeline in a CGAL environment.
+    - [Geographic Information Systems (GIS)](https://doc.cgal.org/5.1/Manual/tuto_gis.html),
+      which demonstrates usage of CGAL data structures and algorithms in the context of a typical GIS application.
+
+    Both tutorials provide complete code.
+
+### [2D and 3D Linear Geometry Kernel](https://doc.cgal.org/5.1/Manual/packages.html#PkgKernel23)
+
+-   Added the functor [`CompareSignedDistanceToLine_2`](https://doc.cgal.org/5.1/Kernel_23/classKernel_1_1CompareSignedDistanceToLine__2.html)
+    to the 2D/3D [`Kernel`](https://doc.cgal.org/5.1/Kernel_23/classKernel.html) concept to compare
+    the signed distance of two points to a line, or the line passing through two given points.
+    Corresponding functors in the model ([`Compare_signed_distance_to_line_2`](https://doc.cgal.org/5.1/Kernel_23/classKernel.html#a066d07dd592ac36ba7ee90988abd349f)) are also added.
+
+### [dD Geometry Kernel](https://doc.cgal.org/5.1/Manual/packages.html#PkgKernelD)
+
+-   The kernels [`Epick_d`](https://doc.cgal.org/5.1/Kernel_d/structCGAL_1_1Epick__d.html)
+    and [`Epeck_d`](https://doc.cgal.org/5.1/Kernel_d/structCGAL_1_1Epeck__d.html) gain two new functors:
+    [`Power_side_of_bounded_power_sphere_d`](https://doc.cgal.org/5.1/Kernel_d/classCGAL_1_1Epeck__d_1_1Power__side__of__bounded__power__sphere__d.html)
+    and [`Compute_squared_radius_smallest_orthogonal_sphere_d`](https://doc.cgal.org/5.1/Kernel_d/classCGAL_1_1Epeck__d_1_1Compute__squared__radius__smallest__orthogonal__sphere__d.html).
+    Those are essential for the computation of weighted alpha-complexes.
+
+### [Surface Mesh](https://doc.cgal.org/5.1/Manual/packages.html#PkgSurfaceMesh)
+
+-   **Breaking change**: The function [`CGAL::Surface_mesh::clear()`](https://doc.cgal.org/5.1/Surface_mesh/classCGAL_1_1Surface__mesh.html#a247d4ad3e6b106ae22e5306203812642)
+    now removes all non-default properties instead of just emptying them.
+
+### [CGAL and the Boost Graph Library (BGL)](https://doc.cgal.org/5.1/Manual/packages.html#PkgBGL)
+
+-   Added the function [`CGAL::alpha_expansion_graphcut()`](https://doc.cgal.org/5.1/BGL/group__PkgBGLPartition.html#ga79c3f58b577af51d1140450729d38f22),
+    which regularizes a multi-label partition over a user-defined graph.
+-   Added the function [`CGAL::regularize_face_selection_borders()`](https://doc.cgal.org/5.1/BGL/group__PkgBGLSelectionFct.html#gac71322b0cc7d7d59447531d5e5e345b6),
+    which uses this alpha expansion graphcut to regularize the borders of a selected faces on a triangle mesh.
+-   Added the function [`CGAL::set_triangulation_ids()`](https://doc.cgal.org/5.1/BGL/group__BGLGraphExternalIndices.html#ga1a22cf8bdde32fcdf1a4a78966eed630),
+    which must be used to initialize vertex, edge, and face indices of a triangulation meant to be used with BGL algorithms.
+
+### [3D Fast Intersection and Distance Computation](https://doc.cgal.org/5.1/Manual/packages.html#PkgAABBTree)
+
+-   The behavior of the internal search tree used to accelerate distance queries has changed:
+    usage of the internal search tree will now be enabled by default, and its construction
+    will be triggered by the first distance query. Automatic construction and usage can be disabled
+    by calling [`CGAL::AABB_tree::do_not_accelerate_distance_queries()`](https://doc.cgal.org/5.1/AABB_tree/classCGAL_1_1AABB__tree.html#abde62f52ccdf411847151aa5000ba4a4)
+    before the first distance query, and the tree can be built at any moment by calling
+    [`CGAL::AABB_tree::accelerate_distance_queries()`](https://doc.cgal.org/5.1/AABB_tree/classCGAL_1_1AABB__tree.html#a5d3877d3f2afbd09341eb4b8c230080b).
+-   **Breaking change**: [`CGAL::AABB_tree::accelerate_distance_queries()`](https://doc.cgal.org/5.1/AABB_tree/classCGAL_1_1AABB__tree.html#a5d3877d3f2afbd09341eb4b8c230080b)
+    and [`CGAL::AABB_tree::do_not_accelerate_distance_queries()`](https://doc.cgal.org/5.1/AABB_tree/classCGAL_1_1AABB__tree.html#abde62f52ccdf411847151aa5000ba4a4)
+    are no longer `const` functions.
+
+### [2D Arrangements](https://doc.cgal.org/5.1/Manual/packages.html#PkgArrangementOnSurface2)
+
+ -   Changed intersection return type from legacy [`CGAL::Object`](https://doc.cgal.org/5.1/STL_Extension/classCGAL_1_1Object.html)
+     to modern `boost::variant` in all traits concepts and models.
+     As there exists an implicit conversion from `boost::variant` to `CGAL::Object`, the
      new code is backward compatible. However, it is recommended that all calls
      to the intersection functions are fixed to use the new return type.
 
-### 2D Regularized Boolean Operations
- -   Changed intersection return type from legacy `CGAL::Object` to modern
-     `boost::variant` in the concept `ArrDirectionalTraits::Intersect_2` and
-     its models..
+### [2D Regularized Boolean Set-Operations](https://doc.cgal.org/5.1/Manual/packages.html#PkgBooleanSetOperations2)
 
-### 2D Minkowski sums
- -   Changed intersection return type from legacy `CGAL::Object` to modern
-     `boost::variant` in the (internally used) model `Arr_labeled_traits_2`.
+ -   Changed intersection return type from legacy [`CGAL::Object`](https://doc.cgal.org/5.1/STL_Extension/classCGAL_1_1Object.html)
+     to modern `boost::variant` in the concept [`ArrDirectionalTraits::Intersect_2`](https://doc.cgal.org/5.1/Boolean_set_operations_2/namespaceArrDirectionalTraits.html)
+     and its models.
 
-### Surface Mesh Topology (new package)
+### [2D Minkowski Sums](https://doc.cgal.org/5.1/Manual/packages.html#PkgMinkowskiSum2)
 
- -   This package allows to compute some topological invariants of
-     surfaces:
-     -  test if two (closed) curves on a combinatorial surface are homotopic. The user can choose between free homotopy and homotopy with fixed endpoints.
-     - test is a curve is contractible.
-     - compute shortest non-contractible cycles on a surface, with or without weights on edges.
+ -   Changed intersection return type from legacy [`CGAL::Object`](https://doc.cgal.org/5.1/STL_Extension/classCGAL_1_1Object.html)
+     to modern `boost::variant` in the (internally used) model `Arr_labeled_traits_2`.
 
-### 3D Fast Intersection and Distance Computation
--   **Breaking change**: the internal search tree is now lazily constructed. To disable it, one must call
-    the new function `do_not_accelerate_distance_queries()` before the first distance query.
+### [dD Spatial Searching](https://doc.cgal.org/5.1/Manual/packages.html#PkgSpatialSearchingD)
 
-### Intersecting Sequences of dD Iso-oriented Boxes 
- -   Added parallel versions of the functions `CGAL::box_intersection_d()` and `CGAL::box_self_intersection_d()`.
+-   The kd-tree can now be built in parallel: [`CGAL::Kd_tree::build()`](https://doc.cgal.org/5.1/Spatial_searching/classCGAL_1_1Kd__tree.html#a8559dbe4d7136fbc8ebab5ee290cbe06)
+    is given an optional template parameter `ConcurrencyTag` (default
+    value remains [`CGAL::Sequential_tag`](https://doc.cgal.org/5.1/STL_Extension/structCGAL_1_1Sequential__tag.html)
+    for backward compatibility).
+-   Improved the performance of the kd-tree in some cases:
+    - Not storing the points coordinates inside the tree usually
+      generates a lot of cache misses, leading to non-optimal
+      performance. This is the case for example
+      when indices are stored inside the tree, or to a lesser extent when the points
+      coordinates are stored in a dynamically allocated array (e.g., [`Epick_d`](https://doc.cgal.org/5.1/Kernel_d/structCGAL_1_1Epick__d.html)
+      with dynamic dimension) &mdash; we says "to a lesser extent" because the points
+      are re-created by the kd-tree in a cache-friendly order after its construction,
+      so the coordinates are more likely to be stored in a near-optimal order
+      on the heap.
+      In these cases, the new `EnablePointsCache` template parameter of the
+      [`CGAL::Kd_tree`](https://doc.cgal.org/5.1/Spatial_searching/classCGAL_1_1Kd__tree.html)
+      class can be set to `CGAL::Tag_true`. The points coordinates
+      will then be cached in an optimal way. This will increase memory
+      consumption but provides better search performance. See the updated
+      [`GeneralDistance`](https://doc.cgal.org/5.1/Spatial_searching/classGeneralDistance.html)
+      and [`FuzzyQueryItem`](https://doc.cgal.org/5.1/Spatial_searching/classFuzzyQueryItem.html)
+      concepts for additional requirements when using such a cache.
+    - In most cases (e.g., Euclidean distance), the distance computation
+      algorithm knows before its end that the distance will be greater
+      than or equal to some given value. This is used in the (orthogonal)
+      k-NN search to interrupt some distance computations before its end,
+      saving precious milliseconds, in particular in medium-to-high dimension.
 
-### CGAL and the Boost Graph Library (BGL)
- -   Introduced the function `set_triangulation_ids(Triangulation& tr)` which must be used to initialize vertex,
-     edge, and face indices of a triangulation meant to be used with BGL algorithms.
- -   Added function `alpha_expansion_graphcut()` which regularizes a
-     multi-label partition over a user-defined graph.
- -   Added function `regularize_face_selection_borders()` which uses
-     this alpha expansion graphcut to regularize the borders of a
-     selected faces on a triangle mesh.
+### [Intersecting Sequences of dD Iso-oriented Boxes](https://doc.cgal.org/5.1/Manual/packages.html#PkgBoxIntersectionD)
 
-### Polygon Mesh Processing
+-   Added parallel versions of the functions
+    [`CGAL::box_intersection_d()`](https://doc.cgal.org/5.1/Box_intersection_d/group__PkgBoxIntersectionD__box__intersection__d.html)
+    and [`CGAL::box_self_intersection_d()`](https://doc.cgal.org/5.1/Box_intersection_d/group__PkgBoxIntersectionD__box__self__intersection__d.html).
 
--   Introduced a new function, `CGAL::Polygon_mesh_processing::remove_connected_components_of_negligible_size()`, 
+### [Spatial Sorting](https://doc.cgal.org/5.1/Manual/packages.html#PkgSpatialSorting)
+
+-   Added parallel versions of the functions
+    [`CGAL::hilbert_sort()`](https://doc.cgal.org/5.1/Spatial_sorting/group__PkgSpatialSortingFunctions.html#ga9da67204747ac19dff65f9c9ff2fca9e)
+    and [`CGAL::spatial_sort()`](https://doc.cgal.org/5.1/Spatial_sorting/group__PkgSpatialSortingFunctions.html#ga7c597c11a3b3859234ff68526cead84d)
+    in 2D and 3D when the median policy is used.
+    The parallel versions use up to four threads in 2D, and up to eight threads in 3D.
+
+### [3D Convex Hulls](https://doc.cgal.org/5.1/Manual/packages.html#PkgConvexHull3)
+
+-   A new overload for [`CGAL::convex_hull_3()`](https://doc.cgal.org/5.1/Convex_hull_3/group__PkgConvexHull3Functions.html#gaa02a3013808fc9a2e5e2f42b9fde8e30)
+    that takes a model of [`VertexListGraph`](https://doc.cgal.org/5.1/BGL/classVertexListGraph.html) has been added.
+-   The long-deprecated function `CGAL::convex_hull_3_to_polyhedron_3()` has been removed.
+    The function [`CGAL::convex_hull_3_to_face_graph()`](https://doc.cgal.org/5.1/Convex_hull_3/group__PkgConvexHull3Functions.html#ga2750f7f197588ed643679835c748c671)
+    should be used instead.
+
+### [Polygon Mesh Processing](https://doc.cgal.org/5.1/Manual/packages.html#PkgPolygonMeshProcessing)
+
+-   Added the function [`CGAL::Polygon_mesh_processing::volume_connected_component()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__orientation__grp.html#ga133e58280959c152770525f27bb42b91),
+    which can be used to get information about the nesting of the connected components of a given triangle mesh and about
+    the volumes defined.
+-   Added the function [`CGAL::Polygon_mesh_processing::remove_connected_components_of_negligible_size()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__repairing__grp.html#gac544fcaba1d59d330a3a1536caff392a),
     which can be used to remove connected components whose area or volume is under a certain threshold.
     Area and volume thresholds are either specified by the user or deduced from the bounding box of the mesh.
--   Added the function `CGAL::Polygon_mesh_processing::volume_connected_component()` that can be used to
-    get information about the nesting of the connected components of a given triangle mesh and about
-    the volumes defined.
--   Added a new named parameter for `keep_large_connected_components()` and `remove_connected_components_of_negligible_size`
-    that can be used to perform a dry run of the operation, meaning that the function will return the number of connected
+-   Added a new named parameter for [`CGAL::Polygon_mesh_processing::keep_large_connected_components()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__keep__connected__components__grp.html#ga48e7b3e6922ee78cf8ce801e3e325d9a)
+    and [`CGAL::Polygon_mesh_processing::remove_connected_components_of_negligible_size`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__repairing__grp.html#gac544fcaba1d59d330a3a1536caff392a),
+    which can be used to perform a dry run of the operation, meaning that the function will return the number of connected
     components that would be removed with the specified threshold, but without actually removing them.
--   The function `CGAL::Polygon_mesh_processing::stitch_borders()` now returns the number
-    of halfedge pairs that were stitched.
--   Introduced the new functions `CGAL::Polygon_mesh_processing::merge_reversible_connected_components()`,
-    `CGAL::Polygon_mesh_processing::duplicate_incompatible_edges_in_polygon_soup()`,
-    and `CGAL::Polygon_mesh_processing::orient_triangle_soup_with_reference_triangle_mesh()` that can be helpful 
-    when repairing a polygon soup.
--   New function to split meshes along a mesh or a plane:
-    `CGAL::Polygon_mesh_processing::split()` 
--   New function to split a single mesh containing several connected components into several meshes containing one connected component:
-    `CGAL::Polygon_mesh_processing::split_connected_components()`
- -   Added parallel versions of the functions `CGAL::Polygon_mesh_processing::does_self_intersect()` 
-     and `CGAL::Polygon_mesh_processing::self_intersections()`.
- -   The function `CGAL::Polygon_mesh_processing::polygon_soup_to_polygon_mesh` now allows passing a point map (for the point range)
-     and a vertex point map (for the polygon mesh) via named parameters.
- -   Added the function `CGAL::Polygon_mesh_processing::polygon_mesh_to_polygon_soup()`.
- -   Added a new function `CGAL::Polygon_mesh_processing::sample_triangle_soup()` that generates points on a triangle soup surface.
+-   Added the function [`CGAL::Polygon_mesh_processing::split()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__corefinement__grp.html#gaa491feee9e41f725332bea0ea1215578),
+    which can be used to split meshes along a mesh or a plane.
+-   Added the function [`CGAL::Polygon_mesh_processing::split_connected_components()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__keep__connected__components__grp.html#ga9ddd1e4b915a4232b1ce5611985302aa)
+    to split a single mesh containing several connected components into several meshes containing one connected component.
+-   Added the functions [`CGAL::Polygon_mesh_processing::merge_reversible_connected_components()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__orientation__grp.html#gae25c1198a89c53d5df2f29dd57fda5ca),
+    [`CGAL::Polygon_mesh_processing::duplicate_non_manifold_edges_in_polygon_soup()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__orientation__grp.html#ga2aa4f7b500dc51d1fc4747705a050946),
+    and [`CGAL::Polygon_mesh_processing::orient_triangle_soup_with_reference_triangle_mesh()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__orientation__grp.html#ga31779672b3afd660664fc9a6c4fdf74d),
+    which can be helpful when repairing a polygon soup.
+-   Added the function [`CGAL::Polygon_mesh_processing::sample_triangle_soup()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__distance__grp.html#gac7af41d13bf1a7c30852be266ac81db5),
+    which generates points on a triangle soup surface.
+-   Added parallel versions of the functions [`CGAL::Polygon_mesh_processing::does_self_intersect()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__intersection__grp.html#gad9fe5d8b433545b69154f43935a11a3b)
+    and [`CGAL::Polygon_mesh_processing::self_intersections()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__intersection__grp.html#gaf19c80ec12cbff7ebe9e69453f1d40b8).
+-   The function [`CGAL::Polygon_mesh_processing::stitch_borders()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__repairing__grp.html#ga8ae4352e67d2b099994ac8990c13bd41)
+    now returns the number of halfedge pairs that were stitched.
+-   Added the function [`CGAL::Polygon_mesh_processing::polygon_mesh_to_polygon_soup()`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__repairing__grp.html#ga76648a509409ff3c3ad3f71eff8ce9d9).
+-   The function [`CGAL::Polygon_mesh_processing::polygon_soup_to_polygon_mesh`](https://doc.cgal.org/5.1/Polygon_mesh_processing/group__PMP__repairing__grp.html#ga0dec58e8a0112791f72ebbe77bac074b)
+    now allows passing a point map (for the point range) and a vertex point map (for the polygon mesh) via named parameters.
 
-### Point Set Processing
- -   Added wrapper functions for registration:
-     - `CGAL::OpenGR::compute_registration_transformation()` computes the registration transformation
-        for two point sets using Super4PCS algorithm implemented in the third party library OpenGR.
-     - `CGAL::OpenGR::register_point_sets()` computes the registration transformation for two point 
-        sets using Super4PCS algorithm implemented in the third party library OpenGR, and registers
-        the points sets by transforming the data point set using the computed transformation.
-     - `CGAL::pointmatcher::compute_registration_transformation()` computes the registration
-        transformation for two point sets using ICP algorithm implemented in the third party library
-        libpointmatcher.
-     - `CGAL::pointmatcher::register_point_sets()` computes the registration transformation for two point
-        sets using ICP algorithm implemented in the third party library libpointmatcher, and registers 
-        the points sets by transforming the data point set using the computed transformation.
+### [Point Set Processing](https://doc.cgal.org/5.1/Manual/packages.html#PkgPointSetProcessing3)
 
+-   **Breaking change:** [`CGAL::remove_outliers()`](https://doc.cgal.org/5.1/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#ga1ab1dcee59caadde50572c5a504cc41a)
+    has been parallelized and thus has a new template parameter `ConcurrencyTag`.
+    To update your code simply add as first template parameter `CGAL::Sequential_tag` or `CGAL::Parallel_tag`
+    when calling this function.
+-   Add a function [`CGAL::cluster_point_set()`](https://doc.cgal.org/5.1/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#gafee41d60b5a257ae034e9157d0af8e46)
+    that segments a point cloud into connected components based on a distance threshold.
+-   Added wrapper functions for registration:
+    - [`CGAL::OpenGR::compute_registration_transformation()`](https://doc.cgal.org/5.1/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#gab81663c718960780ddb176aad845e8cd),
+      which computes the registration transformation for two point sets using the Super4PCS algorithm
+      implemented in the third party library [OpenGR](https://storm-irit.github.io/OpenGR/index.html).
+    - [`CGAL::OpenGR::register_point_sets()`](https://doc.cgal.org/5.1/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#ga6194087f512e4e23dd945a9364d0931d),
+      which computes the registration transformation for two point sets using the Super4PCS algorithm
+      implemented in the third party library [OpenGR](https://storm-irit.github.io/OpenGR/index.html),
+      and registers the points sets by transforming the data point set using the computed transformation.
+    - [`CGAL::pointmatcher::compute_registration_transformation()`](https://doc.cgal.org/5.1/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#gaf75af5c1634fa83fa05a33e95570b127)
+      computes the registration transformation for two point sets using ICP algorithm implemented
+      in the third party library [libpointmatcher](https://github.com/ethz-asl/libpointmatcher).
+    - [`CGAL::pointmatcher::register_point_sets()`](https://doc.cgal.org/5.1/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#gaa222278e20a3ce41930d37326cd54ef9),
+      which computes the registration transformation for two point sets using ICP algorithm implemented
+      in the third party library [libpointmatcher](https://github.com/ethz-asl/libpointmatcher), and registers
+      the points sets by transforming the data point set using the computed transformation.
+
+### [2D Triangulations](https://doc.cgal.org/5.1/Manual/packages.html#PkgTriangulation2)
 
-### 2D Triangulations
 -   To fix an inconsistency between code and documentation and to clarify which types of intersections
-    are truly allowed in constrained Delaunay triangulations, the tag `CGAL::No_intersection_tag`
-    has been deprecated in favor of two new tags `CGAL::No_constraint_intersection_tag`
-    and `CGAL::No_constraint_intersection_requiring_constructions_tag`.
+    are truly allowed in constrained Delaunay triangulations, the tag [`CGAL::No_intersection_tag`](https://doc.cgal.org/5.1/Triangulation_2/structCGAL_1_1No__intersection__tag.html)
+    has been deprecated in favor of two new tags: [`CGAL::No_constraint_intersection_tag`](https://doc.cgal.org/5.1/Triangulation_2/structCGAL_1_1No__constraint__intersection__tag.html)
+    and [`CGAL::No_constraint_intersection_requiring_constructions_tag`](https://doc.cgal.org/5.1/Triangulation_2/structCGAL_1_1No__constraint__intersection__requiring__constructions__tag.html).
     The latter is equivalent to the now-deprecated `CGAL::No_intersection_tag`, and allows constraints
     to intersect as long as no new point has to be created to represent that intersection (for example,
     the intersection of two constraint segments in a 'T'-like junction is an existing point
-    and does not require any new construction). The former tag, `CGAL::No_constraint_intersection_tag`,
+    and as such does not require any new construction). The former tag, `CGAL::No_constraint_intersection_tag`,
     does not allow any intersection, except for the configuration of two constraints having a single
     common endpoints, for convience.
+-   Added the function [`CGAL::split_subconstraint_graph_into_constraints()`](https://doc.cgal.org/5.1/Triangulation_2/classCGAL_1_1Constrained__triangulation__plus__2.html#adea77f5db5cd4dfae302e4502f1caa85)
+    to [`Constrained_triangulation_plus_2`](https://doc.cgal.org/5.1/Triangulation_2/classCGAL_1_1Constrained__triangulation__plus__2.html) to initialize the constraints
+    from a soup of disconnected segments that should first be split into polylines.
 
-### 3D Triangulations
--   The free function `CGAL::file_input()` and the member function `CGAL::Triangulation_3::file_input()` 
-    have been added. The first allows to load a `Triangulation_3` from an input stream, using functors to create vertices and cells.
-    The second is simply the member function version of the first one.
+### [3D Triangulations](https://doc.cgal.org/5.1/Manual/packages.html#PkgTriangulation3)
 
-### 3D Triangulation Data Structure
--   The free function `CGAL::file_input()` and the member function `CGAL::TDS_3::file_input()` 
-    have been added. The first allows to load a `TDS_3` from an input stream, using functors to create vertices and cells.
-    The second is simply the member function version of the first one. 
+-   The member function [`CGAL::Triangulation_3::file_input()`](https://doc.cgal.org/5.1/Triangulation_3/group__PkgIOTriangulation3.html#gadd94d0613e2dd9cdd2e88d2c74d5b1c8)
+    have been added. It allows to load a [`CGAL::Triangulation_3`](https://doc.cgal.org/5.1/Triangulation_3/classCGAL_1_1Triangulation__3.html)
+    from an input stream, using functors to create vertices and cells.
 
-### dD Spatial Searching
+### [3D Triangulation Data Structure](https://doc.cgal.org/5.1/Manual/packages.html#PkgTDS3)
 
--   Improved the performance of the kd-tree in some cases:
-    -   Not storing the points coordinates inside the tree usually
-        generates a lot of cache misses, leading to non-optimal
-        performance. This is the case for example
-        when indices are stored inside the tree, or to a lesser extent when the points
-        coordinates are stored in a dynamically allocated array (e.g., `Epick_d`
-        with dynamic dimension) &mdash; we says "to a lesser extent" because the points
-        are re-created by the kd-tree in a cache-friendly order after its construction,
-        so the coordinates are more likely to be stored in a near-optimal order
-        on the heap.
-        In these cases, the new `EnablePointsCache` template parameter of the
-        `CGAL::Kd_tree` class can be set to `CGAL::Tag_true`. The points coordinates
-        will then be cached in an optimal way. This will increase memory
-        consumption but provides better search performance. See the updated
-        `GeneralDistance` and `FuzzyQueryItem`
-        concepts for additional requirements when using such a cache.
-    -   In most cases (e.g., Euclidean distance), the distance computation
-        algorithm knows before its end that the distance will be greater
-        than or equal to some given value. This is used in the (orthogonal)
-        k-NN search to interrupt some distance computations before its end,
-        saving precious milliseconds, in particular in medium-to-high dimension.
+-   The member function [`CGAL::TDS_3::file_input()`](https://doc.cgal.org/5.1/TDS_3/group__PkgIOTDS3.html#ga381446a02a9240cc83e79c48b37cd119)
+    have been added. It allows to load a [`CGAL::Triangulation_data_structure_3`](https://doc.cgal.org/5.1/TDS_3/classCGAL_1_1Triangulation__data__structure__3.html)
+    from an input stream, using functors to create vertices and cells.
 
-### Spatial Sorting
- -   Added parallel versions of `hilbert_sort()` and `spatial_sort()` in 2D and 3D when the median policy is used.
-     The parallel versions use up to four threads in 2D, and up to eight threads in 3D.
+### [Surface Mesh Simplification](https://doc.cgal.org/5.1/Manual/packages.html#PkgSurfaceMeshSimplification)
 
-### dD Geometry Kernel
--   Epick\_d and Epeck\_d gain 2 new functors: `Power_side_of_bounded_power_sphere_d` and
-    `Compute_squared_radius_smallest_orthogonal_sphere_d`. Those are
-    essential for the computation of weighted alpha-complexes.
+-   Added a [new simplification method](https://doc.cgal.org/5.1/Surface_mesh_simplification/classCGAL_1_1Surface__mesh__simplification_1_1GarlandHeckbert__policies.html)
+    based on the quadric error defined by Garland and Heckbert.
+-   The concept `EdgeProfile` has been removed. This concept was not actually in use as the CGAL-provided model [`CGAL::Edge_profile`](https://doc.cgal.org/5.1/Surface_mesh_simplification/classCGAL_1_1Surface__mesh__simplification_1_1Edge__profile.html)
+    was imposed to the user. Other concepts have been clarified to reflect the fact that the API uses this particular class.
 
-### Surface Mesh Simplification
-- Added a new simplification method based on the quadric error defined by Garland and Heckbert.
-- The concept "EdgeProfile" has been removed. This concept was not actually in use as the CGAL-provided model `CGAL::Edge_profile`
-  was imposed to the user. Other concepts have been clarified to reflect the fact that the API uses this particular class.
+### [STL Extensions for CGAL](https://doc.cgal.org/5.1/Manual/packages.html#PkgSTLExtension)
 
-### STL Extensions for CGAL
- -   Added a new concurrency tag: `CGAL::Parallel_if_available_tag`. This tag is a convenience typedef to `CGAL::Parallel_tag`
-     if the third party library TBB has been found and linked with, and to `CGAL::Sequential_tag` otherwise.
- 
-### Convex_hull_3
-- A new overload for `convex_hull_3()` that takes a model of `VertexListGraph` has been added.
+-   Added a new concurrency tag: [`CGAL::Parallel_if_available_tag`](https://doc.cgal.org/5.1/STL_Extension/structCGAL_1_1Parallel__if__available__tag.html).
+    This tag is a convenience typedef to [`CGAL::Parallel_tag`](https://doc.cgal.org/5.1/STL_Extension/structCGAL_1_1Parallel__tag.html)
+    if the third party library TBB has been found and linked with, and to
+    [`CGAL::Sequential_tag`](https://doc.cgal.org/5.1/STL_Extension/structCGAL_1_1Sequential__tag.html) otherwise.
 
 
 [Release 5.0](https://github.com/CGAL/cgal/releases/tag/releases%2FCGAL-5.0)
@@ -221,13 +273,13 @@ Release date: November 2019
 
 ### [Polygonal Surface Reconstruction](https://doc.cgal.org/5.0/Manual/packages.html#PkgPolygonalSurfaceReconstruction) (new package)
 
- -   This package provides a method for piecewise planar object reconstruction from point clouds. 
-     The method takes as input an unordered point set sampled from a piecewise planar object 
-     and outputs a compact and watertight surface mesh interpolating the input point set. 
-     The method assumes that all necessary major planes are provided (or can be extracted from 
-     the input point set using the shape detection method described in Point Set Shape Detection, 
-     or any other alternative methods).The method can handle arbitrary piecewise planar objects 
-     and is capable of recovering sharp features and is robust to noise and outliers. See also 
+ -   This package provides a method for piecewise planar object reconstruction from point clouds.
+     The method takes as input an unordered point set sampled from a piecewise planar object
+     and outputs a compact and watertight surface mesh interpolating the input point set.
+     The method assumes that all necessary major planes are provided (or can be extracted from
+     the input point set using the shape detection method described in Point Set Shape Detection,
+     or any other alternative methods).The method can handle arbitrary piecewise planar objects
+     and is capable of recovering sharp features and is robust to noise and outliers. See also
      the associated [blog entry](https://www.cgal.org/2019/08/05/Polygonal_surface_reconstruction/).
 
 ### [Shape Detection](https://doc.cgal.org/5.0/Manual/packages.html#PkgShapeDetection) (major changes)
@@ -242,11 +294,11 @@ Release date: November 2019
 ### [2D and 3D Linear Geometry Kernel](https://doc.cgal.org/5.0/Manual/packages.html#PkgKernel23)
  -   Added a new concept, [`ComputeApproximateAngle_3`](https://doc.cgal.org/5.0/Kernel_23/classKernel_1_1ComputeApproximateAngle__3.html),
      to the 3D Kernel concepts to compute the approximate angle between two 3D vectors. Corresponding functors
-     in the model ([`Compute_approximate_angle_3`](https://doc.cgal.org/5.0/Kernel_23/classKernel.html#a183c9ac358a4ccddc04e680f8ed16c0b)) 
+     in the model ([`Compute_approximate_angle_3`](https://doc.cgal.org/5.0/Kernel_23/classKernel.html#a183c9ac358a4ccddc04e680f8ed16c0b))
      and free function ([`approximate_angle`](https://doc.cgal.org/5.0/Kernel_23/group__approximate__angle__grp.html))
      have also been added.
- -   The following objects are now hashable and thus trivially usable 
-     with [`std::unordered_set`](https://en.cppreference.com/w/cpp/container/unordered_set) 
+ -   The following objects are now hashable and thus trivially usable
+     with [`std::unordered_set`](https://en.cppreference.com/w/cpp/container/unordered_set)
      and [`std::unordered_map`](https://en.cppreference.com/w/cpp/header/unordered_map):
      `CGAL::Aff_transformation_2`, `CGAL::Aff_transformation_3`,
      `CGAL::Bbox_2`, `CGAL::Bbox_3`, `CGAL::Circle_2`,
@@ -256,11 +308,11 @@ Release date: November 2019
      `CGAL::Weighted_point_2` and `CGAL::Weighted_point_3`.
 
 ### [Polygon Mesh Processing](https://doc.cgal.org/latest/Manual/packages.html#PkgPolygonMeshProcessing)
- -   Introduced a [wide range of new functions](https://doc.cgal.org/5.0/Polygon_mesh_processing/index.html#title36) 
+ -   Introduced a [wide range of new functions](https://doc.cgal.org/5.0/Polygon_mesh_processing/index.html#title36)
      related to location of queries on a triangle mesh,
      such as [`CGAL::Polygon_mesh_processing::locate(Point, Mesh)`](https://doc.cgal.org/5.0/Polygon_mesh_processing/group__PMP__locate__grp.html#gada09bd8740ba69ead9deca597d53cf15).
      The location of a point on a triangle mesh is expressed as the pair of a face and the barycentric
-     coordinates of the point in this face, enabling robust manipulation of locations 
+     coordinates of the point in this face, enabling robust manipulation of locations
      (for example, intersections of two 3D segments living within the same face).
  -   Added the mesh smoothing function [`smooth_mesh()`](https://doc.cgal.org/5.0/Polygon_mesh_processing/group__PMP__meshing__grp.html#gaa0551d546f6ab2cd9402bea12d8332a3),
      which can be used to improve the quality of triangle elements based on various geometric characteristics.
@@ -283,14 +335,14 @@ Release date: November 2019
      or vertices appearing in multiple umbrellas) of a mesh.
 
 ### [3D Point Set](https://doc.cgal.org/5.0/Manual/packages.html#PkgPointSet3)
- -   The [PLY IO functions](https://doc.cgal.org/5.0/Point_set_3/group__PkgPointSet3IO.html) now take an additional optional parameter to 
+ -   The [PLY IO functions](https://doc.cgal.org/5.0/Point_set_3/group__PkgPointSet3IO.html) now take an additional optional parameter to
      read/write comments from/in the PLY header.
 
 ### [Point Set Processing](https://doc.cgal.org/latest/Manual/packages.html#PkgPointSetProcessing3)
  -   **Breaking change**: the API using iterators and overloads for optional parameters (deprecated since
      CGAL 4.12) has been removed. The current (and now only) API uses ranges and Named Parameters.
  -   Added the possibility to use the named parameter
-     [`neighbor_radius`](https://doc.cgal.org/5.0/Point_set_processing_3/group__psp__namedparameters.html#PSP_neighbor_radius) 
+     [`neighbor_radius`](https://doc.cgal.org/5.0/Point_set_processing_3/group__psp__namedparameters.html#PSP_neighbor_radius)
      to use spherical neighbor queries instead of K-nearest neighbors queries for the following functions:
      [`CGAL::bilateral_smooth_point_set()`](https://doc.cgal.org/5.0/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#ga4f82723e2f0bb33f3677e29e0208a256),
      [`CGAL::jet_estimate_normals()`](https://doc.cgal.org/5.0/Point_set_processing_3/group__PkgPointSetProcessing3Algorithms.html#ga0cd0f87de690d4edf82740e856efa491),
@@ -333,7 +385,7 @@ Release date: November 2019
 ### [3D Triangulations](https://doc.cgal.org/5.0/Manual/packages.html#PkgTriangulation3)
  -   **Breaking change**: The [constructor](https://doc.cgal.org/5.0/Triangulation_3/classCGAL_1_1Triangulation__3.html#a63f67cf6aaadcee14318cf56a36d247a)
      and the [`insert()`](https://doc.cgal.org/5.0/Triangulation_3/classCGAL_1_1Triangulation__3.html#ad3353128386bbb51f79d0263e7f67337)
-     function of [`CGAL::Triangulation_3`](https://doc.cgal.org/5.0/Triangulation_3/classCGAL_1_1Triangulation__3.html) 
+     function of [`CGAL::Triangulation_3`](https://doc.cgal.org/5.0/Triangulation_3/classCGAL_1_1Triangulation__3.html)
      which take a range of points as argument are now guaranteed to
      insert the points following the order of `InputIterator`. Note
      that this change only affects the base class `Triangulation_3`
@@ -345,14 +397,14 @@ Release date: November 2019
 
 ### [Surface Mesh](https://doc.cgal.org/5.0/Manual/packages.html#PkgSurfaceMesh)
  -   Introduced new functions to read and write using the PLY format,
-     [`CGAL::read_ply()`](https://doc.cgal.org/5.0/Surface_mesh/group__PkgSurface__mesh.html#ga42f6ad486ddab74e13d3dc53f511c343) 
-     and [`CGAL::write_ply()`](https://doc.cgal.org/5.0/Surface_mesh/group__PkgSurface__mesh.html#ga77bbb79d449c981895eedb6c3c23bd14), 
+     [`CGAL::read_ply()`](https://doc.cgal.org/5.0/Surface_mesh/group__PkgSurface__mesh.html#ga42f6ad486ddab74e13d3dc53f511c343)
+     and [`CGAL::write_ply()`](https://doc.cgal.org/5.0/Surface_mesh/group__PkgSurface__mesh.html#ga77bbb79d449c981895eedb6c3c23bd14),
      enabling users to save and load additional property maps of the surface mesh.
 
 ###  [CGAL and Solvers](https://doc.cgal.org/5.0/Manual/packages.html#PkgSolverInterface)
  -   Added [concepts](https://doc.cgal.org/5.0/Solver_interface/group__PkgSolverInterfaceConcepts.html)
-     and [models](https://doc.cgal.org/5.0/Solver_interface/group__PkgSolverInterfaceRef.html) 
-     for solving Mixed Integer Programming (MIP) problems with or without constraints. 
+     and [models](https://doc.cgal.org/5.0/Solver_interface/group__PkgSolverInterfaceRef.html)
+     for solving Mixed Integer Programming (MIP) problems with or without constraints.
 
 ### [3D Boolean Operations on Nef Polyhedra](https://doc.cgal.org/5.0/Manual/packages.html#PkgNef3)
  -   Added a function to convert a Nef_polyhedron_3 to a polygon soup: [`CGAL::convert_nef_polyhedron_to_polygon_soup()`](https://doc.cgal.org/5.0/Nef_3/group__PkgNef3IOFunctions.html#ga28a9eb4da0cd6153f0c16f7f9eaf6665)
@@ -381,7 +433,7 @@ Release 4.14
 Release date: March 2019
 
 ### 2D Periodic Hyperbolic Triangulations (new package)
- 
+
  -   This package allows the computation of Delaunay triangulations of
      the Bolza surface.  The Bolza surface is the most symmetric
      hyperbolic surface of genus 2. Its fundamental domain is the
diff --git a/Installation/cmake/modules/CGAL_Boost_iostreams_support.cmake b/Installation/cmake/modules/CGAL_Boost_iostreams_support.cmake
new file mode 100644
index 00000000000..04c8cc5529b
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_Boost_iostreams_support.cmake
@@ -0,0 +1,44 @@
+if(Boost_IOSTREAMS_FOUND AND NOT TARGET CGAL::Boost_iostreams_support)
+
+  if( WIN32 )
+    # to avoid a warning with old cmake
+    set(_Boost_BZIP2_HEADERS             "boost/iostreams/filter/bzip2.hpp")
+    set(_Boost_ZLIB_HEADERS              "boost/iostreams/filter/zlib.hpp")
+    find_package( Boost OPTIONAL_COMPONENTS bzip2 zlib)
+    if (Boost_ZLIB_FOUND AND Boost_BZIP2_FOUND)
+      set(ZLIB_LIBS ${Boost_ZLIB_LIBRARY} ${Boost_BZIP2_LIBRARY})
+    else()
+      message(STATUS "NOTICE: This project requires Boost ZLIB and Boost BZIP2, and will not be compiled.")
+      return()
+    endif()
+
+  else()
+
+    find_package(ZLIB QUIET)
+    if(ZLIB_FOUND)
+      set(ZLIB_LIBS ZLIB::ZLIB)
+    else()
+      message(STATUS "NOTICE: This project requires ZLIB, and will not be compiled.")
+      return()
+    endif()
+
+  endif()
+
+  if(TARGET Boost::iostreams)
+    set(Boost_LIB Boost::iostreams)
+  else()
+    set(Boost_LIB  ${Boost_IOSTREAMS_LIBRARY})
+  endif()
+
+  add_library(CGAL::Boost_iostreams_support INTERFACE IMPORTED)
+
+  if(CMAKE_VERSION VERSION_LESS 3.11)
+    set_target_properties(CGAL::Boost_iostreams_support PROPERTIES
+      INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_BOOST_IOSTREAMS"
+      INTERFACE_LINK_LIBRARIES ${Boost_LIB} ${ZLIB_LIBS})
+  else()
+    set_target_properties(CGAL::Boost_iostreams_support PROPERTIES
+      INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_BOOST_IOSTREAMS")
+    target_link_libraries(CGAL::Boost_iostreams_support INTERFACE ${Boost_LIB} ${ZLIB_LIBS})
+  endif()
+endif()
diff --git a/Installation/cmake/modules/CGAL_Boost_serialization_support.cmake b/Installation/cmake/modules/CGAL_Boost_serialization_support.cmake
new file mode 100644
index 00000000000..84a5ae6657b
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_Boost_serialization_support.cmake
@@ -0,0 +1,12 @@
+if(Boost_SERIALIZATION_FOUND AND NOT TARGET CGAL::Boost_serialization_support)
+  if(TARGET Boost::serialization)
+    set(Boost_LIB Boost::serialization)
+  else()
+    set(Boost_LIB  ${Boost_SERIALIZATION_LIBRARY})
+  endif()
+
+  add_library(CGAL::Boost_serialization_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::Boost_serialization_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_BOOST_SERIALIZATION"
+    INTERFACE_LINK_LIBRARIES ${Boost_LIB})
+endif()
diff --git a/Installation/cmake/modules/CGAL_Common.cmake b/Installation/cmake/modules/CGAL_Common.cmake
index 786763eb01f..ed1fe54ad0c 100644
--- a/Installation/cmake/modules/CGAL_Common.cmake
+++ b/Installation/cmake/modules/CGAL_Common.cmake
@@ -23,7 +23,7 @@ if( NOT CGAL_COMMON_FILE_INCLUDED )
   else()
     set( CMAKE_2_6_3_OR_ABOVE FALSE )
   endif()
-    
+
   if ( CGAL_BUILDING_LIBS )
     option(BUILD_SHARED_LIBS "Build shared libraries" ON)
     set(CGAL_BUILD_SHARED_LIBS ${BUILD_SHARED_LIBS})
@@ -34,7 +34,7 @@ if( NOT CGAL_COMMON_FILE_INCLUDED )
       message( STATUS "Building static libraries" )
     endif()
   endif()
-  
+
   if ( WIN32 )
     find_program(CMAKE_UNAME uname /bin /usr/bin /usr/local/bin )
     if(CMAKE_UNAME)
@@ -61,15 +61,4 @@ if( NOT CGAL_COMMON_FILE_INCLUDED )
   # set use-file for Eigen3 (needed to have default solvers)
   set(EIGEN3_USE_FILE "UseEigen3")
 
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_Boost_IOStreams.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_Boost_Serialization.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_Eigen.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_GLPK.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_LASLIB.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_OpenCV.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_OpenGR.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_pointmatcher.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_SCIP.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_TBB.cmake)
-  include(${CMAKE_CURRENT_LIST_DIR}/CGAL_target_use_TensorFlow.cmake)
 endif()
diff --git a/Installation/cmake/modules/CGAL_Eigen_support.cmake b/Installation/cmake/modules/CGAL_Eigen_support.cmake
new file mode 100644
index 00000000000..5039bd5871a
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_Eigen_support.cmake
@@ -0,0 +1,9 @@
+if(EIGEN3_FOUND AND NOT TARGET CGAL::Eigen_support)
+  if(NOT TARGET Threads::Threads)
+    find_package(Threads REQUIRED)
+  endif()
+  add_library(CGAL::Eigen_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::Eigen_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_EIGEN3_ENABLED"
+    INTERFACE_INCLUDE_DIRECTORIES "${EIGEN3_INCLUDE_DIR}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_GLPK_support.cmake b/Installation/cmake/modules/CGAL_GLPK_support.cmake
new file mode 100644
index 00000000000..391fdf6263f
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_GLPK_support.cmake
@@ -0,0 +1,7 @@
+if(GLPK_FOUND AND NOT TARGET CGAL::GLPK_support)
+  add_library(CGAL::GLPK_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::GLPK_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_USE_GLPK"
+    INTERFACE_INCLUDE_DIRECTORIES "${GLPK_INCLUDE_DIR}"
+    INTERFACE_LINK_LIBRARIES "${GLPK_LIBRARIES}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_LASLIB_support.cmake b/Installation/cmake/modules/CGAL_LASLIB_support.cmake
new file mode 100644
index 00000000000..6b1f6cbb58a
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_LASLIB_support.cmake
@@ -0,0 +1,7 @@
+if(LASLIB_FOUND AND NOT TARGET CGAL::LASLIB_support)
+  add_library(CGAL::LASLIB_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::LASLIB_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_LASLIB"
+    INTERFACE_INCLUDE_DIRECTORIES "${LASLIB_INCLUDE_DIR};${LASZIP_INCLUDE_DIR}"
+    INTERFACE_LINK_LIBRARIES "${LASLIB_LIBRARIES}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_OpenCV_support.cmake b/Installation/cmake/modules/CGAL_OpenCV_support.cmake
new file mode 100644
index 00000000000..84b4e9dd34d
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_OpenCV_support.cmake
@@ -0,0 +1,7 @@
+if(OpenCV_FOUND AND NOT TARGET CGAL::OpenCV_support)
+  add_library(CGAL::OpenCV_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::OpenCV_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_OPENCV"
+    INTERFACE_INCLUDE_DIRECTORIES "${OpenCV_INCLUDE_DIRS}"
+    INTERFACE_LINK_LIBRARIES "${OpenCV_LIBS}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_OpenGR_support.cmake b/Installation/cmake/modules/CGAL_OpenGR_support.cmake
new file mode 100644
index 00000000000..227dda5ec57
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_OpenGR_support.cmake
@@ -0,0 +1,6 @@
+if(OpenGR_FOUND AND NOT TARGET CGAL::OpenGR_support)
+  add_library(CGAL::OpenGR_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::OpenGR_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_OPENGR"
+    INTERFACE_INCLUDE_DIRECTORIES "${OpenGR_INCLUDE_DIR}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_SCIP_support.cmake b/Installation/cmake/modules/CGAL_SCIP_support.cmake
new file mode 100644
index 00000000000..6035b6d64cd
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_SCIP_support.cmake
@@ -0,0 +1,7 @@
+if(SCIP_FOUND AND NOT TARGET CGAL::SCIP_support)
+  add_library(CGAL::SCIP_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::SCIP_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_USE_SCIP"
+    INTERFACE_INCLUDE_DIRECTORIES "${SCIP_INCLUDE_DIRS}"
+    INTERFACE_LINK_LIBRARIES "${SCIP_LIBRARIES}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_SetupCGALDependencies.cmake b/Installation/cmake/modules/CGAL_SetupCGALDependencies.cmake
index f87ee9dda2a..6590e31f940 100644
--- a/Installation/cmake/modules/CGAL_SetupCGALDependencies.cmake
+++ b/Installation/cmake/modules/CGAL_SetupCGALDependencies.cmake
@@ -85,7 +85,7 @@ function(CGAL_setup_CGAL_dependencies target)
     set(keyword PUBLIC)
   endif()
   if(CGAL_DISABLE_GMP)
-    target_compile_definitions(${target} ${keyword} CGAL_DISABLE_GMP=1)    
+    target_compile_definitions(${target} ${keyword} CGAL_DISABLE_GMP=1)
   else()
     use_CGAL_GMP_support(${target} ${keyword})
     set(CGAL_USE_GMP  TRUE CACHE INTERNAL "CGAL library is configured to use GMP")
@@ -95,7 +95,7 @@ function(CGAL_setup_CGAL_dependencies target)
   if(WITH_LEDA)
     use_CGAL_LEDA_support(${target} ${keyword})
   endif()
-  
+
   if (NOT CGAL_HEADER_ONLY)
     target_compile_definitions(${target} ${keyword} CGAL_NOT_HEADER_ONLY=1)
   endif()
@@ -136,6 +136,12 @@ function(CGAL_setup_CGAL_dependencies target)
         $<$<COMPILE_LANGUAGE:CXX>:/bigobj>  # Use /bigobj by default
         )
     endif()
+  elseif ("${CMAKE_CXX_COMPILER_ID}" MATCHES "AppleClang")
+    if (CMAKE_CXX_COMPILER_VERSION VERSION_LESS 11.0.3)
+      message(STATUS "Apple Clang version ${CMAKE_CXX_COMPILER_VERSION} compiler detected")
+      message(STATUS "Boost MP is turned off for all Apple Clang versions below 11.0.3!")
+      target_compile_options(${target} ${keyword} "-DCGAL_DO_NOT_USE_BOOST_MP")
+    endif()
   elseif(CMAKE_CXX_COMPILER_ID MATCHES "Intel")
     message( STATUS "Using Intel Compiler. Adding -fp-model strict" )
     if(WIN32)
diff --git a/Installation/cmake/modules/CGAL_TBB_support.cmake b/Installation/cmake/modules/CGAL_TBB_support.cmake
new file mode 100644
index 00000000000..372f3208578
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_TBB_support.cmake
@@ -0,0 +1,10 @@
+if(TBB_FOUND AND NOT TARGET CGAL::TBB_support)
+  if(NOT TARGET Threads::Threads)
+    find_package(Threads REQUIRED)
+  endif()
+  add_library(CGAL::TBB_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::TBB_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_TBB;NOMINMAX"
+    INTERFACE_INCLUDE_DIRECTORIES "${TBB_INCLUDE_DIRS}"
+    INTERFACE_LINK_LIBRARIES "TBB::tbb;TBB::tbbmalloc;Threads::Threads")
+endif()
diff --git a/Installation/cmake/modules/CGAL_TensorFlow_support.cmake b/Installation/cmake/modules/CGAL_TensorFlow_support.cmake
new file mode 100644
index 00000000000..2a910c1257e
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_TensorFlow_support.cmake
@@ -0,0 +1,7 @@
+if(TensorFlow_FOUND AND NOT TARGET CGAL::TensorFlow_support)
+  add_library(CGAL::TensorFlow_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::TensorFlow_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_TENSORFLOW"
+    INTERFACE_INCLUDE_DIRECTORIES "${TensorFlow_INCLUDE_DIR}"
+    INTERFACE_LINK_LIBRARIES "${TensorFlow_LIBRARY}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_pointmatcher_support.cmake b/Installation/cmake/modules/CGAL_pointmatcher_support.cmake
new file mode 100644
index 00000000000..c023102661f
--- /dev/null
+++ b/Installation/cmake/modules/CGAL_pointmatcher_support.cmake
@@ -0,0 +1,7 @@
+if(libpointmatcher_FOUND AND NOT TARGET CGAL::pointmatcher_support)
+  add_library(CGAL::pointmatcher_support INTERFACE IMPORTED)
+  set_target_properties(CGAL::pointmatcher_support PROPERTIES
+    INTERFACE_COMPILE_DEFINITIONS "CGAL_LINKED_WITH_POINTMATCHER"
+    INTERFACE_INCLUDE_DIRECTORIES "${libpointmatcher_INCLUDE_DIR}"
+    INTERFACE_LINK_LIBRARIES "${libpointmatcher_LIBRARIES}")
+endif()
diff --git a/Installation/cmake/modules/CGAL_target_use_Boost_IOStreams.cmake b/Installation/cmake/modules/CGAL_target_use_Boost_IOStreams.cmake
deleted file mode 100644
index 57077271398..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_Boost_IOStreams.cmake
+++ /dev/null
@@ -1,41 +0,0 @@
-if (CGAL_target_use_Boost_IOStreams_included)
-  return()
-endif()
-set(CGAL_target_use_Boost_IOStreams_included TRUE)
-
-function(CGAL_target_use_Boost_IOStreams target)
-
-  if( WIN32 )
-    # to avoid a warning with old cmake
-    set(_Boost_BZIP2_HEADERS             "boost/iostreams/filter/bzip2.hpp")
-    set(_Boost_ZLIB_HEADERS              "boost/iostreams/filter/zlib.hpp")
-    find_package( Boost OPTIONAL_COMPONENTS bzip2 zlib)
-  else()
-    find_package(ZLIB QUIET)
-  endif()
-
-  if(TARGET Boost::iostreams)
-    target_link_libraries(${target} PUBLIC Boost::iostreams)
-  else()
-    target_link_libraries(${target} PUBLIC ${Boost_IOSTREAMS_LIBRARY})
-  endif()
-
-  if( WIN32 )
-    if (Boost_ZLIB_FOUND AND Boost_BZIP2_FOUND)
-      target_link_libraries(${target} PUBLIC ${Boost_ZLIB_LIBRARY} ${Boost_BZIP2_LIBRARY})
-    else()
-      message(STATUS "NOTICE: This project requires Boost ZLIB and Boost BZIP2, and will not be compiled.")
-      return()
-    endif()
-  else()
-    if(ZLIB_FOUND)
-      target_link_libraries(${target} PUBLIC ZLIB::ZLIB)
-    else()
-      message(STATUS "NOTICE: This project requires ZLIB, and will not be compiled.")
-      return()
-    endif()
-  endif()
-
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_BOOST_IOSTREAMS)
-
-endfunction()
diff --git a/Installation/cmake/modules/CGAL_target_use_Boost_Serialization.cmake b/Installation/cmake/modules/CGAL_target_use_Boost_Serialization.cmake
deleted file mode 100644
index 2bf47b467ff..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_Boost_Serialization.cmake
+++ /dev/null
@@ -1,16 +0,0 @@
-if (CGAL_target_use_Boost_Serialization_included)
-  return()
-endif()
-set(CGAL_target_use_Boost_Serialization_included TRUE)
-
-function(CGAL_target_use_Boost_Serialization target)
-
-  if(TARGET Boost::serialization)
-    target_link_libraries(${target} PUBLIC Boost::serialization)
-  else()
-    target_link_libraries(${target} PUBLIC ${Boost_SERIALIZATION_LIBRARY})
-  endif()
-
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_BOOST_SERIALIZATION)
-
-endfunction()
diff --git a/Installation/cmake/modules/CGAL_target_use_Eigen.cmake b/Installation/cmake/modules/CGAL_target_use_Eigen.cmake
deleted file mode 100644
index 84f9f3be721..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_Eigen.cmake
+++ /dev/null
@@ -1,13 +0,0 @@
-if (CGAL_target_use_Eigen_included)
-  return()
-endif()
-set(CGAL_target_use_Eigen_included TRUE)
-
-set( Eigen3_FIND_VERSION "3.1.0")
-set(EIGEN3_USE_FILE "UseEigen3")
-
-function(CGAL_target_use_Eigen target)
-  target_include_directories(${target} PUBLIC ${EIGEN3_INCLUDE_DIR})
-  target_compile_options( ${target} PUBLIC -DCGAL_EIGEN3_ENABLED)
-endfunction()
-
diff --git a/Installation/cmake/modules/CGAL_target_use_GLPK.cmake b/Installation/cmake/modules/CGAL_target_use_GLPK.cmake
deleted file mode 100644
index f19bd315b16..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_GLPK.cmake
+++ /dev/null
@@ -1,11 +0,0 @@
-if (CGAL_target_use_GLPK_included)
-  return()
-endif()
-set(CGAL_target_use_GLPK_included TRUE)
-
-function(CGAL_target_use_GLPK target)
-  target_include_directories(${target} PUBLIC ${GLPK_INCLUDE_DIR})
-  target_compile_options(${target} PUBLIC -DCGAL_USE_GLPK)
-  target_link_libraries(${target} PUBLIC ${GLPK_LIBRARIES})
-endfunction()
-
diff --git a/Installation/cmake/modules/CGAL_target_use_LASLIB.cmake b/Installation/cmake/modules/CGAL_target_use_LASLIB.cmake
deleted file mode 100644
index 65ad9084e5a..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_LASLIB.cmake
+++ /dev/null
@@ -1,11 +0,0 @@
-if (CGAL_target_use_LASLIB_included)
-  return()
-endif()
-set(CGAL_target_use_LASLIB_included TRUE)
-
-function(CGAL_target_use_LASLIB target)
-  target_include_directories(${target} PUBLIC ${LASLIB_INCLUDE_DIR})
-  target_include_directories(${target} PUBLIC ${LASZIP_INCLUDE_DIR})
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_LASLIB)
-  target_link_libraries(${target} PUBLIC ${LASLIB_LIBRARIES})
-endfunction()
diff --git a/Installation/cmake/modules/CGAL_target_use_OpenCV.cmake b/Installation/cmake/modules/CGAL_target_use_OpenCV.cmake
deleted file mode 100644
index d378d50aead..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_OpenCV.cmake
+++ /dev/null
@@ -1,10 +0,0 @@
-if (CGAL_target_use_OpenCV_included)
-  return()
-endif()
-set(CGAL_target_use_OpenCV_included TRUE)
-
-function(CGAL_target_use_OpenCV target)
-  target_include_directories(${target} PUBLIC ${OpenCV_INCLUDE_DIRS})
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_OPENCV)
-  target_link_libraries(${target} PUBLIC ${OpenCV_LIBS})
-endfunction()
diff --git a/Installation/cmake/modules/CGAL_target_use_OpenGR.cmake b/Installation/cmake/modules/CGAL_target_use_OpenGR.cmake
deleted file mode 100644
index dc6044f8926..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_OpenGR.cmake
+++ /dev/null
@@ -1,9 +0,0 @@
-if (CGAL_target_use_OpenGR_included)
-  return()
-endif()
-set(CGAL_target_use_OpenGR_included TRUE)
-
-function(CGAL_target_use_OpenGR target)
-  target_include_directories(${target} PUBLIC ${OpenGR_INCLUDE_DIR})
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_OPENGR)
-endfunction()
diff --git a/Installation/cmake/modules/CGAL_target_use_SCIP.cmake b/Installation/cmake/modules/CGAL_target_use_SCIP.cmake
deleted file mode 100644
index 354216bb1f7..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_SCIP.cmake
+++ /dev/null
@@ -1,11 +0,0 @@
-if (CGAL_target_use_SCIP_included)
-  return()
-endif()
-set(CGAL_target_use_SCIP_included TRUE)
-
-function(CGAL_target_use_SCIP target)
-  target_include_directories(${target} PUBLIC ${SCIP_INCLUDE_DIRS})
-  target_compile_options(${target} PUBLIC -DCGAL_USE_SCIP)
-  target_link_libraries(${target} PUBLIC ${SCIP_LIBRARIES})
-endfunction()
-
diff --git a/Installation/cmake/modules/CGAL_target_use_TBB.cmake b/Installation/cmake/modules/CGAL_target_use_TBB.cmake
index 76c41c4ec25..5f68060eea5 100644
--- a/Installation/cmake/modules/CGAL_target_use_TBB.cmake
+++ b/Installation/cmake/modules/CGAL_target_use_TBB.cmake
@@ -6,7 +6,9 @@ set(CGAL_target_use_TBB_included TRUE)
 set(TBB_USE_FILE "UseTBB")
 
 function(CGAL_target_use_TBB target)
-  if(NOT TARGET Threads::Threads)
+  message(DEPRECATION "This file CGAL_target_use_TBB.cmake is deprecated, and the imported target `CGAL::TBB_support` from CGAL_TBB_support.cmake should be used instead.")
+  if(NOT TARGET
+      Threads::Threads)
     find_package(Threads REQUIRED)
   endif()
   target_link_libraries( ${target} PUBLIC TBB::tbb TBB::tbbmalloc Threads::Threads)
diff --git a/Installation/cmake/modules/CGAL_target_use_TensorFlow.cmake b/Installation/cmake/modules/CGAL_target_use_TensorFlow.cmake
deleted file mode 100644
index 80bda689dab..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_TensorFlow.cmake
+++ /dev/null
@@ -1,10 +0,0 @@
-if (CGAL_target_use_TensorFlow_included)
-  return()
-endif()
-set(CGAL_target_use_TensorFlow_included TRUE)
-
-function(CGAL_target_use_TensorFlow target)
-  target_include_directories(${target} PUBLIC ${TensorFlow_INCLUDE_DIR})
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_TENSORFLOW)
-  target_link_libraries(${target} PUBLIC ${TensorFlow_LIBRARU})
-endfunction()
diff --git a/Installation/cmake/modules/CGAL_target_use_pointmatcher.cmake b/Installation/cmake/modules/CGAL_target_use_pointmatcher.cmake
deleted file mode 100644
index 5047815a336..00000000000
--- a/Installation/cmake/modules/CGAL_target_use_pointmatcher.cmake
+++ /dev/null
@@ -1,10 +0,0 @@
-if (CGAL_target_use_pointmatcher_included)
-  return()
-endif()
-set(CGAL_target_use_pointmatcher_included TRUE)
-
-function(CGAL_target_use_pointmatcher target)
-  target_include_directories(${target} PUBLIC ${libpointmatcher_INCLUDE_DIR})
-  target_compile_options( ${target} PUBLIC -DCGAL_LINKED_WITH_POINTMATCHER)
-  target_link_libraries(${target} PUBLIC ${libpointmatcher_LIBRARIES})
-endfunction()
diff --git a/Installation/cmake/modules/UseEigen3.cmake b/Installation/cmake/modules/UseEigen3.cmake
index 850bb638392..ccdb6682bd7 100644
--- a/Installation/cmake/modules/UseEigen3.cmake
+++ b/Installation/cmake/modules/UseEigen3.cmake
@@ -8,4 +8,4 @@ add_definitions(-DCGAL_EIGEN3_ENABLED)
 
 set (EIGEN3_SETUP TRUE)
 
-message(DEPRECATION "This file UseEigen.cmake is deprecated, and the function `CGAL_target_use_Eigen` from CGAL_target_use_Eigen.cmake should be used instead.")
+message(DEPRECATION "This file UseEigen.cmake is deprecated, and the imported target `CGAL::Eigen_support` from CGAL_Eigen_support.cmake should be used instead.")
diff --git a/Installation/cmake/modules/UseLASLIB.cmake b/Installation/cmake/modules/UseLASLIB.cmake
index 99f3374a24f..1af7a023ceb 100644
--- a/Installation/cmake/modules/UseLASLIB.cmake
+++ b/Installation/cmake/modules/UseLASLIB.cmake
@@ -3,5 +3,4 @@
 
 add_definitions(-DCGAL_LINKED_WITH_LASLIB)
 
-message(DEPRECATION "This file UseLASLIB.cmake is deprecated, and the function `CGAL_target_use_LASLIB` from CGAL_target_use_LASLIB.cmake should be used instead.")
-
+message(DEPRECATION "This file UseLASLIB.cmake is deprecated, and the imported target `CGAL::TBB_support` from CGAL_LASLIB_support.cmake should be used instead.")
diff --git a/Installation/cmake/modules/UseTBB.cmake b/Installation/cmake/modules/UseTBB.cmake
index 5a22f6f079a..a1322a2f3a6 100644
--- a/Installation/cmake/modules/UseTBB.cmake
+++ b/Installation/cmake/modules/UseTBB.cmake
@@ -5,4 +5,4 @@ include_directories ( ${TBB_INCLUDE_DIRS} )
 link_directories( ${TBB_LIBRARY_DIRS} )
 add_definitions( -DNOMINMAX -DCGAL_LINKED_WITH_TBB )
 
-message(DEPRECATION "This file UseTBB.cmake is deprecated, and the function `CGAL_target_use_TBB` from CGAL_target_use_TBB.cmake should be used instead.")
+message(DEPRECATION "This file UseTBB.cmake is deprecated, and the imported target `CGAL::TBB_support` from CGAL_TBB_support.cmake should be used instead.")
diff --git a/Installation/include/CGAL/config.h b/Installation/include/CGAL/config.h
index a215cbbf4e5..2b00c7d6e15 100644
--- a/Installation/include/CGAL/config.h
+++ b/Installation/include/CGAL/config.h
@@ -36,6 +36,10 @@
 #  define WIN64
 #endif
 
+#ifdef BOOST_MSVC
+#define _SILENCE_CXX17_ALLOCATOR_VOID_DEPRECATION_WARNING 1
+#endif
+
 #ifdef CGAL_INCLUDE_WINDOWS_DOT_H
 // Mimic users including this file which defines min max macros
 // and other names leading to name clashes
@@ -101,6 +105,10 @@
 // <boost/type_traits/detail/has_postfix_operator.hpp> fails as well
 #  define BOOST_TT_HAS_POST_DECREMENT_HPP_INCLUDED
 #  define BOOST_TT_HAS_POST_INCREMENT_HPP_INCLUDED
+//work around for moc bug : https://bugreports.qt.io/browse/QTBUG-80990
+#if defined(CGAL_LINKED_WITH_TBB)
+#undef CGAL_LINKED_WITH_TBB
+#endif
 #endif
 
 // Macro used by Boost Parameter. Mesh_3 needs at least 12, before the
@@ -546,13 +554,9 @@ using std::max;
 #endif
 
 // Macro to specify a 'noreturn' attribute.
-#if defined(__GNUG__) || __has_attribute(__noreturn__)
-#  define CGAL_NORETURN  __attribute__ ((__noreturn__))
-#elif defined (_MSC_VER)
-#  define CGAL_NORETURN __declspec(noreturn)
-#else
-#  define CGAL_NORETURN
-#endif
+// (This macro existed in CGAL before we switched to C++11. Let's keep
+// the macro defined for backward-compatibility. That cannot harm.)
+#define CGAL_NORETURN  [[noreturn]]
 
 // Macro to specify [[no_unique_address]] if supported
 #if __has_cpp_attribute(no_unique_address)
@@ -740,5 +744,4 @@ typedef const void * Nullptr_t;   // Anticipate C++0x's std::nullptr_t
 /// @}
 #include <CGAL/license/lgpl.h>
 
-
 #endif // CGAL_CONFIG_H
diff --git a/Installation/include/CGAL/license/Tetrahedral_remeshing.h b/Installation/include/CGAL/license/Tetrahedral_remeshing.h
new file mode 100644
index 00000000000..10c8d9e138d
--- /dev/null
+++ b/Installation/include/CGAL/license/Tetrahedral_remeshing.h
@@ -0,0 +1,54 @@
+// Copyright (c) 2016  GeometryFactory SARL (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
+//
+// Author(s) : Andreas Fabri
+//
+// Warning: this file is generated, see include/CGAL/licence/README.md
+
+#ifndef CGAL_LICENSE_TETRAHEDRAL_REMESHING_H
+#define CGAL_LICENSE_TETRAHEDRAL_REMESHING_H
+
+#include <CGAL/config.h>
+#include <CGAL/license.h>
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE
+
+#  if CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE < CGAL_RELEASE_DATE
+
+#    if defined(CGAL_LICENSE_WARNING)
+
+       CGAL_pragma_warning("Your commercial license for CGAL does not cover "
+                           "this release of the Tetrahedral Remeshing package.")
+#    endif
+
+#    ifdef CGAL_LICENSE_ERROR
+#      error "Your commercial license for CGAL does not cover this release \
+              of the Tetrahedral Remeshing package. \
+              You get this error, as you defined CGAL_LICENSE_ERROR."
+#    endif // CGAL_LICENSE_ERROR
+
+#  endif // CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE < CGAL_RELEASE_DATE
+
+#else // no CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE
+
+#  if defined(CGAL_LICENSE_WARNING)
+     CGAL_pragma_warning("\nThe macro CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE is not defined."
+                          "\nYou use the CGAL Tetrahedral Remeshing package under "
+                          "the terms of the GPLv3+.")
+#  endif // CGAL_LICENSE_WARNING
+
+#  ifdef CGAL_LICENSE_ERROR
+#    error "The macro CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE is not defined.\
+            You use the CGAL Tetrahedral Remeshing package under the terms of \
+            the GPLv3+. You get this error, as you defined CGAL_LICENSE_ERROR."
+#  endif // CGAL_LICENSE_ERROR
+
+#endif // no CGAL_TETRAHEDRAL_REMESHING_COMMERCIAL_LICENSE
+
+#endif // CGAL_LICENSE_TETRAHEDRAL_REMESHING_H
diff --git a/Installation/include/CGAL/license/gpl_package_list.txt b/Installation/include/CGAL/license/gpl_package_list.txt
index 57a8ac6662c..f249f09b1ac 100644
--- a/Installation/include/CGAL/license/gpl_package_list.txt
+++ b/Installation/include/CGAL/license/gpl_package_list.txt
@@ -93,3 +93,4 @@ Triangulation_3 3D Triangulations
 Triangulation dD Triangulations
 Visibility_2 2D Visibility Computation
 Voronoi_diagram_2 2D Voronoi Diagram Adaptor
+Tetrahedral_remeshing Tetrahedral Remeshing
diff --git a/Installation/include/CGAL/version.h b/Installation/include/CGAL/version.h
index 85ff9e71cad..26a92686edd 100644
--- a/Installation/include/CGAL/version.h
+++ b/Installation/include/CGAL/version.h
@@ -17,12 +17,12 @@
 #define CGAL_VERSION_H
 
 #ifndef SWIG
-#define CGAL_VERSION 5.1
+#define CGAL_VERSION 5.1-beta2
 #define CGAL_GIT_HASH abcdef
 #endif
 #define CGAL_VERSION_NR 1050100000
 #define CGAL_SVN_REVISION 99999
-#define CGAL_RELEASE_DATE 20191108
+#define CGAL_RELEASE_DATE 20200609
 
 #include <CGAL/version_macros.h>
 
diff --git a/Installation/lib/cmake/CGAL/CGALConfigVersion.cmake b/Installation/lib/cmake/CGAL/CGALConfigVersion.cmake
index 52b3b35c8bf..e0ff35433ce 100644
--- a/Installation/lib/cmake/CGAL/CGALConfigVersion.cmake
+++ b/Installation/lib/cmake/CGAL/CGALConfigVersion.cmake
@@ -1,7 +1,7 @@
 set(CGAL_MAJOR_VERSION 5)
 set(CGAL_MINOR_VERSION 1)
 set(CGAL_BUGFIX_VERSION 0)
-set(CGAL_VERSION_PUBLIC_RELEASE_VERSION "5.1-dev")
+set(CGAL_VERSION_PUBLIC_RELEASE_VERSION "5.1-beta2")
 set(CGAL_VERSION_PUBLIC_RELEASE_NAME "CGAL-${CGAL_VERSION_PUBLIC_RELEASE_VERSION}")
 
 if (CGAL_BUGFIX_VERSION AND CGAL_BUGFIX_VERSION GREATER 0)
@@ -15,7 +15,11 @@ set(PACKAGE_VERSION ${CGAL_CREATED_VERSION_NUM})
 if(PACKAGE_VERSION VERSION_LESS PACKAGE_FIND_VERSION)
   set(PACKAGE_VERSION_COMPATIBLE FALSE)
 else()
-  set(PACKAGE_VERSION_COMPATIBLE TRUE)
+  if(PACKAGE_FIND_VERSION_MAJOR STREQUAL CGAL_MAJOR_VERSION)
+    set(PACKAGE_VERSION_COMPATIBLE TRUE)
+  else()
+    set(PACKAGE_VERSION_COMPATIBLE FALSE)
+  endif()
   if(PACKAGE_FIND_VERSION STREQUAL PACKAGE_VERSION)
     set(PACKAGE_VERSION_EXACT TRUE)
   endif()
diff --git a/Installation/test/Installation/CMakeLists.txt b/Installation/test/Installation/CMakeLists.txt
index 8a1b401bce6..eeb855c2b3f 100644
--- a/Installation/test/Installation/CMakeLists.txt
+++ b/Installation/test/Installation/CMakeLists.txt
@@ -48,9 +48,10 @@ if ( CGAL_FOUND )
   endif()
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
   create_single_source_cgal_program( "test_TBB.cpp" )
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(test_TBB)
+  if(TARGET CGAl::TBB_support)
+    target_link_libraries(test_TBB PUBLIC CGAL::TBB_support)
   endif()
 
   create_link_to_program(CGAL)
@@ -103,7 +104,10 @@ endif()
 function(CGAL_installation_test_find_package_version mode)
   set(EXACT)
   if(mode STREQUAL "less")
-    MATH(EXPR CGAL_MAJOR_VERSION "${CGAL_MAJOR_VERSION} - 1")
+    set(CGAL_MINOR_VERSION 0)
+  endif()
+  if(mode STREQUAL "less_major")
+    set(CGAL_MAJOR_VERSION 0)
   endif()
   if(mode STREQUAL "greater" OR mode STREQUAL "fail-exact")
     MATH(EXPR CGAL_MINOR_VERSION "${CGAL_MINOR_VERSION} + 1")
@@ -121,16 +125,18 @@ function(CGAL_installation_test_find_package_version mode)
   file(MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/test_find_package_version_${mode})
   configure_file(test_find_package.cmake.in ${CMAKE_CURRENT_BINARY_DIR}/test_find_package_version_${mode}/CMakeLists.txt)
   add_test(NAME test_find_package_version_${mode}
-    COMMAND ${CMAKE_COMMAND} -S ${CMAKE_CURRENT_BINARY_DIR}/test_find_package_version_${mode} -B ${CMAKE_CURRENT_BINARY_DIR}/build-test_find_package_version_${mode})
+    COMMAND ${CMAKE_COMMAND} -S ${CMAKE_CURRENT_BINARY_DIR}/test_find_package_version_${mode} -B ${CMAKE_CURRENT_BINARY_DIR}/build-test_find_package_version_${mode} -DCGAL_DO_NOT_WARN_ABOUT_CMAKE_BUILD_TYPE=ON)
   cgal_setup_test_properties(test_find_package_version_${mode})
 endfunction()
 
 CGAL_installation_test_find_package_version(less)
+CGAL_installation_test_find_package_version(less_major)
 CGAL_installation_test_find_package_version(equal)
 CGAL_installation_test_find_package_version(greater)
 CGAL_installation_test_find_package_version(exact)
 CGAL_installation_test_find_package_version(fail-exact)
 set_tests_properties(
   test_find_package_version_greater
+  test_find_package_version_less_major
   test_find_package_version_fail-exact
   PROPERTIES WILL_FAIL TRUE)
diff --git a/Interpolation/include/CGAL/interpolation_functions.h b/Interpolation/include/CGAL/interpolation_functions.h
index 58780776458..0c672580504 100644
--- a/Interpolation/include/CGAL/interpolation_functions.h
+++ b/Interpolation/include/CGAL/interpolation_functions.h
@@ -34,7 +34,7 @@ struct Data_access
   typedef typename Map::mapped_type   Data_type;
   typedef typename Map::key_type      Key_type;
 
-  Data_access<Map>(const Map& m): map(m){}
+  Data_access(const Map& m): map(m){}
 
   std::pair< Data_type, bool>
   operator()(const Key_type& p) const
diff --git a/Interval_skip_list/include/CGAL/Interval_skip_list.h b/Interval_skip_list/include/CGAL/Interval_skip_list.h
index 33a2ad9f195..a445981a3f2 100644
--- a/Interval_skip_list/include/CGAL/Interval_skip_list.h
+++ b/Interval_skip_list/include/CGAL/Interval_skip_list.h
@@ -115,7 +115,7 @@ class Interval_for_container : public Interval_
       {}
 
       void *   for_compact_container() const { return p; }
-      void * & for_compact_container()       { return p; }
+      void for_compact_container(void *ptr) { p = ptr; }
     };
 
 
@@ -457,7 +457,7 @@ class Interval_for_container : public Interval_
   public:
 #ifdef CGAL_ISL_USE_CCC
     void *   for_compact_container() const { return p; }
-    void * & for_compact_container()       { return p; }
+    void for_compact_container(void *ptr) { p = ptr; }
 #endif
 
     bool operator==(const IntervalListElt& e)
diff --git a/Jet_fitting_3/examples/Jet_fitting_3/CMakeLists.txt b/Jet_fitting_3/examples/Jet_fitting_3/CMakeLists.txt
index b52c55f79a3..74595d7724f 100644
--- a/Jet_fitting_3/examples/Jet_fitting_3/CMakeLists.txt
+++ b/Jet_fitting_3/examples/Jet_fitting_3/CMakeLists.txt
@@ -13,7 +13,8 @@ if ( CGAL_FOUND )
 
   # use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     # Link with Boost.ProgramOptions (optional)
     find_package(Boost QUIET COMPONENTS program_options)
     if(Boost_PROGRAM_OPTIONS_FOUND)
@@ -30,9 +31,9 @@ if ( CGAL_FOUND )
    endif()
 
    create_single_source_cgal_program( "Mesh_estimation.cpp" )
-   CGAL_target_use_Eigen(Mesh_estimation)
+   target_link_libraries(Mesh_estimation PUBLIC CGAL::Eigen_support)
    create_single_source_cgal_program( "Single_estimation.cpp" )
-   CGAL_target_use_Eigen(Single_estimation)
+   target_link_libraries(Single_estimation PUBLIC CGAL::Eigen_support)
 
   else()
     message(STATUS "NOTICE: This program requires Eigen 3.1 (or greater) and will not be compiled.")
@@ -43,4 +44,3 @@ else()
   message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Jet_fitting_3/test/Jet_fitting_3/CMakeLists.txt b/Jet_fitting_3/test/Jet_fitting_3/CMakeLists.txt
index feff5e7bb7a..2ff8f62b541 100644
--- a/Jet_fitting_3/test/Jet_fitting_3/CMakeLists.txt
+++ b/Jet_fitting_3/test/Jet_fitting_3/CMakeLists.txt
@@ -13,9 +13,10 @@ if ( CGAL_FOUND )
 
   # use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "blind_1pt.cpp" )
-    CGAL_target_use_Eigen(blind_1pt)
+    target_link_libraries(blind_1pt PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "NOTICE: This program requires Eigen 3.1 (or greater) and will not be compiled.")
   endif()
@@ -25,4 +26,3 @@ else()
   message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Kernel_23/include/CGAL/determinant.h b/Kernel_23/include/CGAL/determinant.h
index fe14a2d1974..f470720d560 100644
--- a/Kernel_23/include/CGAL/determinant.h
+++ b/Kernel_23/include/CGAL/determinant.h
@@ -202,6 +202,204 @@ determinant(
   return m012345;
 }
 
+template <class RT>
+RT
+determinant(
+ const RT& a00, const RT& a01, const RT& a02, const RT& a03, const RT& a04, const RT& a05, const RT& a06,
+ const RT& a10, const RT& a11, const RT& a12, const RT& a13, const RT& a14, const RT& a15, const RT& a16,
+ const RT& a20, const RT& a21, const RT& a22, const RT& a23, const RT& a24, const RT& a25, const RT& a26,
+ const RT& a30, const RT& a31, const RT& a32, const RT& a33, const RT& a34, const RT& a35, const RT& a36,
+ const RT& a40, const RT& a41, const RT& a42, const RT& a43, const RT& a44, const RT& a45, const RT& a46,
+ const RT& a50, const RT& a51, const RT& a52, const RT& a53, const RT& a54, const RT& a55, const RT& a56,
+ const RT& a60, const RT& a61, const RT& a62, const RT& a63, const RT& a64, const RT& a65, const RT& a66)
+{
+// First compute the det2x2
+  const RT m01 = a00*a11 - a10*a01;
+  const RT m02 = a00*a21 - a20*a01;
+  const RT m03 = a00*a31 - a30*a01;
+  const RT m04 = a00*a41 - a40*a01;
+  const RT m05 = a00*a51 - a50*a01;
+  const RT m06 = a00*a61 - a60*a01;
+
+  const RT m12 = a10*a21 - a20*a11;
+  const RT m13 = a10*a31 - a30*a11;
+  const RT m14 = a10*a41 - a40*a11;
+  const RT m15 = a10*a51 - a50*a11;
+  const RT m16 = a10*a61 - a60*a11;
+
+  const RT m23 = a20*a31 - a30*a21;
+  const RT m24 = a20*a41 - a40*a21;
+  const RT m25 = a20*a51 - a50*a21;
+  const RT m26 = a20*a61 - a60*a21;
+
+  const RT m34 = a30*a41 - a40*a31;
+  const RT m35 = a30*a51 - a50*a31;
+  const RT m36 = a30*a61 - a60*a31;
+
+  const RT m45 = a40*a51 - a50*a41;
+  const RT m46 = a40*a61 - a60*a41;
+
+  const RT m56 = a50*a61 - a60*a51;
+
+// Now compute the minors of rank 3
+  const RT m012 = m01*a22 - m02*a12 + m12*a02;
+  const RT m013 = m01*a32 - m03*a12 + m13*a02;
+  const RT m014 = m01*a42 - m04*a12 + m14*a02;
+  const RT m015 = m01*a52 - m05*a12 + m15*a02;
+  const RT m016 = m01*a62 - m06*a12 + m16*a02;
+
+  const RT m023 = m02*a32 - m03*a22 + m23*a02;
+  const RT m024 = m02*a42 - m04*a22 + m24*a02;
+  const RT m025 = m02*a52 - m05*a22 + m25*a02;
+  const RT m026 = m02*a62 - m06*a22 + m26*a02;
+  const RT m034 = m03*a42 - m04*a32 + m34*a02;
+  const RT m035 = m03*a52 - m05*a32 + m35*a02;
+  const RT m036 = m03*a62 - m06*a32 + m36*a02;
+
+  const RT m045 = m04*a52 - m05*a42 + m45*a02;
+  const RT m046 = m04*a62 - m06*a42 + m46*a02;
+
+  const RT m056 = m05*a62 - m06*a52 + m56*a02;
+
+
+  const RT m123 = m12*a32 - m13*a22 + m23*a12;
+  const RT m124 = m12*a42 - m14*a22 + m24*a12;
+  const RT m125 = m12*a52 - m15*a22 + m25*a12;
+  const RT m126 = m12*a62 - m16*a22 + m26*a12;
+
+  const RT m134 = m13*a42 - m14*a32 + m34*a12;
+  const RT m135 = m13*a52 - m15*a32 + m35*a12;
+  const RT m136 = m13*a62 - m16*a32 + m36*a12;
+
+  const RT m145 = m14*a52 - m15*a42 + m45*a12;
+  const RT m146 = m14*a62 - m16*a42 + m46*a12;
+
+  const RT m156 = m15*a62 - m16*a52 + m56*a12;
+
+  const RT m234 = m23*a42 - m24*a32 + m34*a22;
+  const RT m235 = m23*a52 - m25*a32 + m35*a22;
+  const RT m236 = m23*a62 - m26*a32 + m36*a22;
+
+  const RT m245 = m24*a52 - m25*a42 + m45*a22;
+  const RT m246 = m24*a62 - m26*a42 + m46*a22;
+
+  const RT m256 = m25*a62 - m26*a52 + m56*a22;
+
+  const RT m345 = m34*a52 - m35*a42 + m45*a32;
+  const RT m346 = m34*a62 - m36*a42 + m46*a32;
+
+  const RT m356 = m35*a62 - m36*a52 + m56*a32;
+
+  const RT m456 = m45*a62 - m46*a52 + m56*a42;
+
+// Now compute the minors of rank 4
+  const RT m0123 = m012*a33 - m013*a23 + m023*a13 - m123*a03;
+
+  const RT m0124 = m012*a43 - m014*a23 + m024*a13 - m124*a03;
+  const RT m0125 = m012*a53 - m015*a23 + m025*a13 - m125*a03;
+  const RT m0126 = m012*a63 - m016*a23 + m026*a13 - m126*a03;
+
+  const RT m0134 = m013*a43 - m014*a33 + m034*a13 - m134*a03;
+  const RT m0135 = m013*a53 - m015*a33 + m035*a13 - m135*a03;
+  const RT m0136 = m013*a63 - m016*a33 + m036*a13 - m136*a03;
+
+  const RT m0145 = m014*a53 - m015*a43 + m045*a13 - m145*a03;
+  const RT m0146 = m014*a63 - m016*a43 + m046*a13 - m146*a03;
+
+  const RT m0156 = m015*a63 - m016*a53 + m056*a13 - m156*a03;
+
+  const RT m0234 = m023*a43 - m024*a33 + m034*a23 - m234*a03;
+  const RT m0235 = m023*a53 - m025*a33 + m035*a23 - m235*a03;
+  const RT m0236 = m023*a63 - m026*a33 + m036*a23 - m236*a03;
+
+  const RT m0245 = m024*a53 - m025*a43 + m045*a23 - m245*a03;
+  const RT m0246 = m024*a63 - m026*a43 + m046*a23 - m246*a03;
+
+  const RT m0256 = m025*a63 - m026*a53 + m056*a23 - m256*a03;
+
+  const RT m0345 = m034*a53 - m035*a43 + m045*a33 - m345*a03;
+  const RT m0346 = m034*a63 - m036*a43 + m046*a33 - m346*a03;
+
+  const RT m0356 = m035*a63 - m036*a53 + m056*a33 - m356*a03;
+
+  const RT m0456 = m045*a63 - m046*a53 + m056*a43 - m456*a03;
+
+  const RT m1234 = m123*a43 - m124*a33 + m134*a23 - m234*a13;
+  const RT m1235 = m123*a53 - m125*a33 + m135*a23 - m235*a13;
+  const RT m1236 = m123*a63 - m126*a33 + m136*a23 - m236*a13;
+
+  const RT m1245 = m124*a53 - m125*a43 + m145*a23 - m245*a13;
+  const RT m1246 = m124*a63 - m126*a43 + m146*a23 - m246*a13;
+
+  const RT m1256 = m125*a63 - m126*a53 + m156*a23 - m256*a13;
+
+  const RT m1345 = m134*a53 - m135*a43 + m145*a33 - m345*a13;
+  const RT m1346 = m134*a63 - m136*a43 + m146*a33 - m346*a13;
+
+  const RT m1356 = m135*a63 - m136*a53 + m156*a33 - m356*a13;
+  const RT m1456 = m145*a63 - m146*a53 + m156*a43 - m456*a13;
+
+  const RT m2345 = m234*a53 - m235*a43 + m245*a33 - m345*a23;
+  const RT m2346 = m234*a63 - m236*a43 + m246*a33 - m346*a23;
+
+  const RT m2356 = m235*a63 - m236*a53 + m256*a33 - m356*a23;
+  const RT m2456 = m245*a63 - m246*a53 + m256*a43 - m456*a23;
+
+  const RT m3456 = m345*a63 - m346*a53 + m356*a43 - m456*a33;
+
+
+  // Now compute the minors of rank 5
+  const RT m01234 = m0123*a44 - m0124*a34 + m0134*a24 - m0234*a14 + m1234*a04;
+
+  const RT m01235 = m0123*a54 - m0125*a34 + m0135*a24 - m0235*a14 + m1235*a04;
+
+  const RT m01236 = m0123*a64 - m0126*a34 + m0136*a24 - m0236*a14 + m1236*a04;
+
+  const RT m01245 = m0124*a54 - m0125*a44 + m0145*a24 - m0245*a14 + m1245*a04;
+  const RT m01246 = m0124*a64 - m0126*a44 + m0146*a24 - m0246*a14 + m1246*a04;
+
+  const RT m01256 = m0125*a64 - m0126*a54 + m0156*a24 - m0256*a14 + m1256*a04;
+
+  const RT m01345 = m0134*a54 - m0135*a44 + m0145*a34 - m0345*a14 + m1345*a04;
+  const RT m01346 = m0134*a64 - m0136*a44 + m0146*a34 - m0346*a14 + m1346*a04;
+
+  const RT m01356 = m0135*a64 - m0136*a54 + m0156*a34 - m0356*a14 + m1356*a04;
+  const RT m01456 = m0145*a64 - m0146*a54 + m0156*a44 - m0456*a14 + m1456*a04;
+
+  const RT m02345 = m0234*a54 - m0235*a44 + m0245*a34 - m0345*a24 + m2345*a04;
+  const RT m02346 = m0234*a64 - m0236*a44 + m0246*a34 - m0346*a24 + m2346*a04;
+
+  const RT m02356 = m0235*a64 - m0236*a54 + m0256*a34 - m0356*a24 + m2356*a04;
+  const RT m02456 = m0245*a64 - m0246*a54 + m0256*a44 - m0456*a24 + m2456*a04;
+  const RT m03456 = m0345*a64 - m0346*a54 + m0356*a44 - m0456*a34 + m3456*a04;
+
+  const RT m12345 = m1234*a54 - m1235*a44 + m1245*a34 - m1345*a24 + m2345*a14;
+  const RT m12346 = m1234*a64 - m1236*a44 + m1246*a34 - m1346*a24 + m2346*a14;
+
+
+  const RT m12356 = m1235*a64 - m1236*a54 + m1256*a34 - m1356*a24 + m2356*a14;
+  const RT m12456 = m1245*a64 - m1246*a54 + m1256*a44 - m1456*a24 + m2456*a14;
+  const RT m13456 = m1345*a64 - m1346*a54 + m1356*a44 - m1456*a34 + m3456*a14;
+
+  const RT m23456 = m2345*a64 - m2346*a54 + m2356*a44 - m2456*a34 + m3456*a24;
+
+// Now compute the minors of rank 6
+  const RT m012345 = m01234*a55 - m01235*a45 + m01245*a35 - m01345*a25 + m02345*a15 - m12345*a05;
+  const RT m012346 = m01234*a65 - m01236*a45 + m01246*a35 - m01346*a25 + m02346*a15 - m12346*a05;
+  const RT m012356 = m01235*a65 - m01236*a55 + m01256*a35 - m01356*a25 + m02356*a15 - m12356*a05;
+  const RT m012456 = m01245*a65 - m01246*a55 + m01256*a45 - m01456*a25 + m02456*a15 - m12456*a05;
+  const RT m013456 = m01345*a65 - m01346*a55 + m01356*a45 - m01456*a35 + m03456*a15 - m13456*a05;
+  const RT m023456 = m02345*a65 - m02346*a55 + m02356*a45 - m02456*a35 + m03456*a25 - m23456*a05;
+  const RT m123456 = m12345*a65 - m12346*a55 + m12356*a45 - m12456*a35 + m13456*a25 - m23456*a15;
+
+
+  // Now compute the minors of rank 7
+  const RT m0123456 = m012345 * a66 - m012346 * a56 + m012356 * a46 -  m012456 * a36 + m013456 * a26 - m023456 * a16 + m123456 * a06;
+
+  return m0123456;
+}
+
+
 } //namespace CGAL
 
 #endif // CGAL_DETERMINANT_H
diff --git a/Kernel_23/test/Kernel_23/determinant_77.cpp b/Kernel_23/test/Kernel_23/determinant_77.cpp
new file mode 100644
index 00000000000..c48be9908d8
--- /dev/null
+++ b/Kernel_23/test/Kernel_23/determinant_77.cpp
@@ -0,0 +1,121 @@
+#include <CGAL/determinant.h>
+#include <CGAL/Random.h>
+
+#include <boost/lexical_cast.hpp>
+
+#include <iostream>
+
+using CGAL::determinant;
+
+template <typename RT>
+RT det_77_alt(const RT& a00, const RT& a01, const RT& a02, const RT& a03, const RT& a04, const RT& a05, const RT& a06,
+              const RT& a10, const RT& a11, const RT& a12, const RT& a13, const RT& a14, const RT& a15, const RT& a16,
+              const RT& a20, const RT& a21, const RT& a22, const RT& a23, const RT& a24, const RT& a25, const RT& a26,
+              const RT& a30, const RT& a31, const RT& a32, const RT& a33, const RT& a34, const RT& a35, const RT& a36,
+              const RT& a40, const RT& a41, const RT& a42, const RT& a43, const RT& a44, const RT& a45, const RT& a46,
+              const RT& a50, const RT& a51, const RT& a52, const RT& a53, const RT& a54, const RT& a55, const RT& a56,
+              const RT& a60, const RT& a61, const RT& a62, const RT& a63, const RT& a64, const RT& a65, const RT& a66)
+{
+  const RT r1 = a06 * determinant(
+                  a10, a11, a12, a13, a14, a15,
+                                  a20, a21, a22, a23, a24, a25,
+                                  a30, a31, a32, a33, a34, a35,
+                                  a40, a41, a42, a43, a44, a45,
+                                  a50, a51, a52, a53, a54, a55,
+                                  a60, a61, a62, a63, a64, a65);
+
+  const RT r2 = - a16 * determinant(a00, a01, a02, a03, a04, a05,
+
+                                    a20, a21, a22, a23, a24, a25,
+                                    a30, a31, a32, a33, a34, a35,
+                                    a40, a41, a42, a43, a44, a45,
+                                    a50, a51, a52, a53, a54, a55,
+                                    a60, a61, a62, a63, a64, a65);
+
+  const RT r3 = a26 * determinant(a00, a01, a02, a03, a04, a05,
+                                  a10, a11, a12, a13, a14, a15,
+
+                                  a30, a31, a32, a33, a34, a35,
+                                  a40, a41, a42, a43, a44, a45,
+                                  a50, a51, a52, a53, a54, a55,
+                                  a60, a61, a62, a63, a64, a65);
+
+  const RT r4 = - a36 * determinant(a00, a01, a02, a03, a04, a05,
+                                    a10, a11, a12, a13, a14, a15,
+                                    a20, a21, a22, a23, a24, a25,
+
+                                    a40, a41, a42, a43, a44, a45,
+                                    a50, a51, a52, a53, a54, a55,
+                                    a60, a61, a62, a63, a64, a65);
+
+  const RT r5 = a46 * determinant(a00, a01, a02, a03, a04, a05,
+                                  a10, a11, a12, a13, a14, a15,
+                                  a20, a21, a22, a23, a24, a25,
+                                  a30, a31, a32, a33, a34, a35,
+
+                                  a50, a51, a52, a53, a54, a55,
+                                  a60, a61, a62, a63, a64, a65);
+
+  const RT r6 = - a56 * determinant(a00, a01, a02, a03, a04, a05,
+                                    a10, a11, a12, a13, a14, a15,
+                                    a20, a21, a22, a23, a24, a25,
+                                    a30, a31, a32, a33, a34, a35,
+                                    a40, a41, a42, a43, a44, a45,
+
+                                    a60, a61, a62, a63, a64, a65);
+
+  const RT r7 = a66 * determinant(a00, a01, a02, a03, a04, a05,
+                                  a10, a11, a12, a13, a14, a15,
+                                  a20, a21, a22, a23, a24, a25,
+                                  a30, a31, a32, a33, a34, a35,
+                                  a40, a41, a42, a43, a44, a45,
+                                  a50, a51, a52, a53, a54, a55
+
+                                  );
+
+  return r1 + r2 + r3 + r4 + r5 + r6 + r7;
+}
+
+int main(int, char**)
+{
+  assert(determinant<int>(4, 5, 1, 4, 6, 3, 1,
+                          4, 3, 6, 4, 2, 7, 3,
+                          6, 3, 3, 6, 2, 4, 5,
+                          1, 4, 3, 5, 5, 6 ,1,
+                          1, 3, 2, 7, 9, 6, 1,
+                          7, 6, 5, 4, 6, 2, 2,
+                          2, 3, 5, 7, 4, 3, 3) == 763);
+
+  CGAL::Random rnd;
+  std::cout << "Seed: " << rnd.get_seed() << std::endl;
+
+  for(int k=0; k<100; ++k)
+  {
+    std::array<std::array<int, 7>, 7> mat;
+    for(int i=0; i<7; ++i)
+      for(int j=0; j<7; ++j)
+        mat[i][j] = rnd.get_int(-18, 18);
+
+    const int det_1 = determinant<int>(mat[0][0], mat[0][1], mat[0][2], mat[0][3], mat[0][4], mat[0][5], mat[0][6],
+                                       mat[1][0], mat[1][1], mat[1][2], mat[1][3], mat[1][4], mat[1][5], mat[1][6],
+                                       mat[2][0], mat[2][1], mat[2][2], mat[2][3], mat[2][4], mat[2][5], mat[2][6],
+                                       mat[3][0], mat[3][1], mat[3][2], mat[3][3], mat[3][4], mat[3][5], mat[3][6],
+                                       mat[4][0], mat[4][1], mat[4][2], mat[4][3], mat[4][4], mat[4][5], mat[4][6],
+                                       mat[0][0], mat[5][1], mat[5][2], mat[5][3], mat[5][4], mat[5][5], mat[5][6],
+                                       mat[6][0], mat[6][1], mat[6][2], mat[6][3], mat[6][4], mat[6][5], mat[6][6]);
+
+    const int det_2 = det_77_alt<int>(mat[0][0], mat[0][1], mat[0][2], mat[0][3], mat[0][4], mat[0][5], mat[0][6],
+                                      mat[1][0], mat[1][1], mat[1][2], mat[1][3], mat[1][4], mat[1][5], mat[1][6],
+                                      mat[2][0], mat[2][1], mat[2][2], mat[2][3], mat[2][4], mat[2][5], mat[2][6],
+                                      mat[3][0], mat[3][1], mat[3][2], mat[3][3], mat[3][4], mat[3][5], mat[3][6],
+                                      mat[4][0], mat[4][1], mat[4][2], mat[4][3], mat[4][4], mat[4][5], mat[4][6],
+                                      mat[0][0], mat[5][1], mat[5][2], mat[5][3], mat[5][4], mat[5][5], mat[5][6],
+                                      mat[6][0], mat[6][1], mat[6][2], mat[6][3], mat[6][4], mat[6][5], mat[6][6]);
+
+    std::cout << "dets: " << det_1 << " " << det_2 << std::endl;
+    assert(det_1 == det_2);
+  }
+
+  std::cout << "Done!" << std::endl;
+  return EXIT_SUCCESS;
+}
diff --git a/Maintenance/infrastructure/cgal.geometryfactory.com/crontab b/Maintenance/infrastructure/cgal.geometryfactory.com/crontab
index d98d42b770d..8de3a49b3ae 100644
--- a/Maintenance/infrastructure/cgal.geometryfactory.com/crontab
+++ b/Maintenance/infrastructure/cgal.geometryfactory.com/crontab
@@ -23,13 +23,13 @@ LC_CTYPE=en_US.UTF-8
 # The script also updates the manual tools.
 
 # "master" alone
-0 21  *  *  Sun                      cd $HOME/CGAL/create_internal_release && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/master.git --do-it || echo ERROR
+0 21  *  *  Sun                      cd $HOME/CGAL/create_internal_release && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/master.git --do-it --beta 2 --public || echo ERROR
 # "integration"
-0 21  *  *  Mon,Tue,Wed,Thu,Fri      cd $HOME/CGAL/create_internal_release && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/integration.git $HOME/CGAL/branches/empty-dir --do-it --public || echo ERROR
+0 21  *  *  Mon,Wed,Thu,Fri      cd $HOME/CGAL/create_internal_release && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/integration.git $HOME/CGAL/branches/empty-dir --do-it --beta 2 --public || echo ERROR
 # from branch 5.0
 0 21  *  *  Sat                      cd $HOME/CGAL/create_internal_release-5.0-branch && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/CGAL-5.0-branch.git --public --do-it || echo ERROR
 # from branch 4.14
-#0 21  *  *  Sat                      cd $HOME/CGAL/create_internal_release-4.14-branch && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/CGAL-4.14-branch.git --public --do-it || echo ERROR
+0 21  *  *  Tue                      cd $HOME/CGAL/create_internal_release-4.14-branch && /usr/bin/time scl enable rh-git29 -- $HOME/bin/create_release $HOME/CGAL/branches/CGAL-4.14-branch.git --public --do-it || echo ERROR
 
 ## Older stuff
 # from branch 4.13
diff --git a/Maintenance/public_release/announcement/mailing-beta.eml b/Maintenance/public_release/announcement/mailing-beta.eml
index 11251b7563a..9234c02b647 100644
--- a/Maintenance/public_release/announcement/mailing-beta.eml
+++ b/Maintenance/public_release/announcement/mailing-beta.eml
@@ -1,111 +1,124 @@
-Subject: CGAL 5.0 Beta 2 Released, Computational Geometry Algorithms Library
+Subject: CGAL 5.1 Beta 1 Released, Computational Geometry Algorithms Library
 Content-Type: text/plain; charset="utf-8"
-Body: 
+Body:
 
-The CGAL Open Source Project is pleased to announce the release 5.0 Beta 2
+The CGAL Open Source Project is pleased to announce the release 5.1 Beta 1
 of CGAL, the Computational Geometry Algorithms Library.
 
 
-CGAL version 5.0 Beta 2 is a public testing release. It should provide a
+CGAL version 5.1 Beta 1 is a public testing release. It should provide a
 solid ground to report bugs that need to be tackled before the release
-of the final version of CGAL 5.0 in November.
-
-The important changes since CGAL 5.0 Beta 1 are the fix of CMake
-issues, with header-only installations, and the update of the section
-“Getting Started with CGAL” of the documentation.
+of the final version of CGAL 5.1 in July.
 
 
 Besides fixes and general enhancement to existing packages, the following
-has changed since CGAL 4.14:
-
-General changes
-
--   CGAL 5.0 is the first release of CGAL that requires a C++ compiler
-    with the support of C++14 or later. The new list of supported
-    compilers is:
-    -   Visual C++ 14.0 (from Visual Studio 2015 Update 3) or later,
-    -   Gnu g++ 6.3 or later (on Linux or MacOS),
-    -   LLVM Clang version 8.0 or later (on Linux or MacOS), and
-    -   Apple Clang compiler versions 7.0.2 and 10.0.1 (on MacOS).
--   Since CGAL 4.9, CGAL can be used as a header-only library, with
-    dependencies. Since CGAL 5.0, that is now the default, unless
-    specified differently in the (optional) CMake configuration.
--   The section “Getting Started with CGAL” of the documentation has
-    been updated and reorganized.
--   The minimal version of Boost is now 1.57.0.
-
-Polygonal Surface Reconstruction (new package)
-
--   This package provides a method for piecewise planar object
-    reconstruction from point clouds. The method takes as input an
-    unordered point set sampled from a piecewise planar object and
-    outputs a compact and watertight surface mesh interpolating the
-    input point set. The method assumes that all necessary major planes
-    are provided (or can be extracted from the input point set using the
-    shape detection method described in Point Set Shape Detection, or
-    any other alternative methods).The method can handle arbitrary
-    piecewise planar objects and is capable of recovering sharp features
-    and is robust to noise and outliers. See also the associated blog
-    entry:
-    
-      https://www.cgal.org/2019/08/05/Polygonal_surface_reconstruction/
+has changed since CGAL 5.0:
 
 
-Shape Detection (major changes)
+Tetrahedral Remeshing (new package)
 
--   BREAKING CHANGE: The concept ShapeDetectionTraits has been renamed
-    to EfficientRANSACTraits.
--   BREAKING CHANGE: The Shape_detection_3 namespace has been renamed to
-    Shape_detection.
--   Added a new, generic implementation of region growing. This enables
-    for example applying region growing to inputs such as 2D and 3D
-    point sets, or models of the FaceGraph concept. Learn more about
-    this new algorithm with this blog entry:
-    
-      https://www.cgal.org/2019/07/30/Shape_detection/
+-   This package implements a tetrahedral isotropic remeshing algorithm,
+    that improves the quality of tetrahedra in terms of dihedral angles,
+    while targeting a given edge length.
 
+Surface Mesh Topology (new package)
 
-dD Geometry Kernel
+-   This package enables the computation of some topological invariants
+    of surfaces, such as:
+    -   test if two (closed) curves on a combinatorial surface are
+        homotopic. Users can choose between free homotopy and homotopy
+        with fixed endpoints;
+    -   test is a curve is contractible;
+    -   compute shortest non-contractible cycles on a surface, with or
+        without weights on edges.
 
--   A new exact kernel, Epeck_d, is now available.
+    See also the associated blog entry:
+      https://www.cgal.org/2020/05/08/Surface_mesh_topology/
 
+Optimal Bounding Box (new package)
 
-2D and 3D Triangulations
+-   This package implements an optimization algorithm that aims to
+    construct a close approximation of the _optimal bounding box_ of a
+    mesh or a point set, which is defined as the smallest (in terms of
+    volume) bounding box that contains a given mesh or point set.
 
--   BREAKING CHANGE: Several deprecated functions and classes have been
-    removed. See the full list of breaking changes in the release notes.
+    See also the associated blog entry:
+      https://www.cgal.org/2020/04/20/Optimal_bounding_box/
 
--   BREAKING CHANGE: The constructor and the insert() function of
-    CGAL::Triangulation_2 or CGAL::Triangulation_3 which take a range of
-    points as argument are now guaranteed to insert the points following
-    the order of InputIterator. Note that this change only affects the
-    base class CGAL::Triangulation_[23] and not any derived class, such
-    as CGAL::Delaunay_triangulation_[23].
+Tutorials
 
-Polygon Mesh Processing
+-   Two new, detailed tutorials have been added:
+    -   Surface Reconstruction from Point Clouds, which goes over a
+        typical full processing pipeline in a CGAL environment.
+    -   Geographic Information Systems (GIS), which demonstrates usage
+        of CGAL data structures and algorithms in the context of a
+        typical GIS application.
 
--   Introduced a wide range of new functions related to location of
-    queries on a triangle mesh, such as
-    CGAL::Polygon_mesh_processing::locate(Point, Mesh). The location of
-    a point on a triangle mesh is expressed as the pair of a face and
-    the barycentric coordinates of the point in this face, enabling
-    robust manipulation of locations (for example, intersections of two
-    3D segments living within the same face).
--   Added the mesh smoothing function smooth_mesh(), which can be used
-    to improve the quality of triangle elements based on various
-    geometric characteristics.
--   Added the shape smoothing function smooth_shape(), which can be used
-    to smooth the surface of a triangle mesh, using the mean curvature
-    flow to perform noise removal.
+    Both tutorials provide complete code.
 
+    See https://doc.cgal.org/5.1/Manual/tutorials.html
 
 Point Set Processing
 
--   BREAKING CHANGE: the API using iterators and overloads for optional
-    parameters (deprecated since CGAL 4.12) has been removed. The
-    current (and now only) API uses ranges and Named Parameters.
+-   Added wrapper functions for registration, using the Super4PCS and
+    ICP algorithms implemented in the third party libraries OpenGR and
+    libpointmatcher.
 
-See https://www.cgal.org/2019/10/31/cgal50-beta2/ for a complete list of
+
+Surface Mesh Simplification
+
+-   Added a new simplification method based on the quadric error defined
+    by Garland and Heckbert.
+
+dD Spatial Searching
+
+-   The kd-tree can now be built in parallel: CGAL::Kd_tree::build() is
+    given an optional template parameter ConcurrencyTag (default value
+    remains CGAL::Sequential_tag for backward compatibility).
+
+Intersecting Sequences of dD Iso-oriented Boxes
+
+-   Added parallel versions of the functions CGAL::box_intersection_d()
+    and CGAL::box_self_intersection_d().
+
+Polygon Mesh Processing
+
+-   Added the function CGAL::Polygon_mesh_processing::split(), which can
+    be used to split meshes along a mesh or a plane.
+-   Added the function
+    CGAL::Polygon_mesh_processing::split_connected_components() to split
+    a single mesh containing several connected components into several
+    meshes containing one connected component.
+-   Added parallel versions of the functions
+    CGAL::Polygon_mesh_processing::does_self_intersect() and
+    CGAL::Polygon_mesh_processing::self_intersections().
+-   Added several mesh repair functions (see the complete changelog for
+    more information).
+
+3D Fast Intersection and Distance Computation
+
+-   The behavior of the internal search tree used to accelerate distance
+    queries has changed: usage of the internal search tree will now be
+    enabled by default, and its construction will be triggered by the
+    first distance query. Automatic construction and usage can be
+    disabled by calling
+    CGAL::AABB_tree::do_not_accelerate_distance_queries() before the
+    first distance query, and the tree can be built at any moment by
+    calling CGAL::AABB_tree::accelerate_distance_queries().
+-   BREAKING CHANGE: CGAL::AABB_tree::accelerate_distance_queries() and
+    CGAL::AABB_tree::do_not_accelerate_distance_queries() are no longer
+    const functions.
+
+
+CGAL and the Boost Graph Library (BGL)
+
+-   Added the function CGAL::alpha_expansion_graphcut(), which
+    regularizes a multi-label partition over a user-defined graph.
+-   Added the function CGAL::regularize_face_selection_borders(), which
+    uses this alpha expansion graphcut to regularize the borders of a
+    selected faces on a triangle mesh.
+
+See https://www.cgal.org/2020/06/09/cgal51-beta1/ for a complete list of
 changes.
 
 
diff --git a/Mesh_2/include/CGAL/Delaunay_mesh_face_base_2.h b/Mesh_2/include/CGAL/Delaunay_mesh_face_base_2.h
index 696edc53ba8..b706db459d6 100644
--- a/Mesh_2/include/CGAL/Delaunay_mesh_face_base_2.h
+++ b/Mesh_2/include/CGAL/Delaunay_mesh_face_base_2.h
@@ -17,6 +17,7 @@
 
 
 #include <CGAL/Constrained_Delaunay_triangulation_face_base_2.h>
+#include <CGAL/Has_timestamp.h>
 
 namespace CGAL {
 
@@ -67,6 +68,14 @@ public:
   /** compatibility with CGAL-3.2 */
   inline
   void set_marked(const bool b) { in_domain=b; }
+
+  typedef Tag_true Has_timestamp;
+
+  std::size_t time_stamp() const { return time_stamp_; }
+
+  void set_time_stamp(const std::size_t& ts) { time_stamp_ = ts; }
+
+  std::size_t time_stamp_;
 };
 
 } // namespace CGAL
diff --git a/Mesh_2/test/Mesh_2/reproductibility.cpp b/Mesh_2/test/Mesh_2/reproductibility.cpp
new file mode 100644
index 00000000000..bb470c98b67
--- /dev/null
+++ b/Mesh_2/test/Mesh_2/reproductibility.cpp
@@ -0,0 +1,90 @@
+//#define CGAL_MESH_2_DEBUG_BAD_FACES
+//#define CGAL_MESH_2_DEBUG_CLUSTERS
+
+#include <CGAL/Constrained_Delaunay_triangulation_2.h>
+#include <CGAL/Delaunay_mesh_size_criteria_2.h>
+#include <CGAL/Delaunay_mesh_face_base_2.h>
+#include <CGAL/Delaunay_mesher_2.h>
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <fstream>
+#include <sstream>
+#include <iostream>
+#include <string>
+
+using K = CGAL::Exact_predicates_inexact_constructions_kernel;
+using Vb = CGAL::Triangulation_vertex_base_2<K>;
+using Fb = CGAL::Delaunay_mesh_face_base_2<K>;
+using Tds = CGAL::Triangulation_data_structure_2<Vb, Fb>;
+using CDT = CGAL::Constrained_Delaunay_triangulation_2<K, Tds, CGAL::Exact_predicates_tag>;
+using Criteria = CGAL::Delaunay_mesh_size_criteria_2<CDT>;
+using Mesher =  CGAL::Delaunay_mesher_2<CDT, Criteria>;
+
+using Vertex_handle = CDT::Vertex_handle;
+using Point = CDT::Point;
+
+int main(int, char**)
+{
+  auto triangulate = [](int index)
+  {
+    CDT cdt;
+
+    Vertex_handle va = cdt.insert(Point(-0.74397572, -0.54545455));
+    Vertex_handle vb = cdt.insert(Point(-0.13526831, -1));
+    Vertex_handle vc = cdt.insert(Point(0.067634156, -1));
+    Vertex_handle vd = cdt.insert(Point(0.33817078, -0.54545455));
+    Vertex_handle ve = cdt.insert(Point(0.74397572, 0.27272727));
+    Vertex_handle vf = cdt.insert(Point(0.74397572, 0.54545455));
+    Vertex_handle vg = cdt.insert(Point(0.067634156, 1));
+    Vertex_handle vh = cdt.insert(Point(-0.13526831, 1));
+    Vertex_handle vi = cdt.insert(Point(-0.74397572, -0.18181818));
+
+    cdt.insert_constraint(va, vb);
+    cdt.insert_constraint(vb, vc);
+    cdt.insert_constraint(vc, vd);
+    cdt.insert_constraint(vd, ve);
+    cdt.insert_constraint(ve, vf);
+    cdt.insert_constraint(vf, vg);
+    cdt.insert_constraint(vg, vh);
+    cdt.insert_constraint(vh, vi);
+    cdt.insert_constraint(vi, va);
+
+    const std::vector<Point> points{
+      Point(0.65605132, 0.43821259),
+      Point(0.23073753, -0.4476739),
+      Point(-0.037496007, -0.93636364),
+      Point(-0.00095596601, 0.88181818),
+      Point(-0.62452925, -0.30720903),
+      Point(-0.69663181, -0.45045525),
+    };
+
+    cdt.insert(points.cbegin(), points.cend());
+
+    std::cout << "Meshing: " << index << std::endl;
+
+    std::cout << "Number of vertices before: " << cdt.number_of_vertices() << std::endl;
+
+    Mesher mesher(cdt);
+    mesher.set_criteria(Criteria(0.125, 0.05*std::sqrt(2)));
+
+    mesher.refine_mesh();
+
+    std::cout << "Number of vertices after: " << cdt.number_of_vertices() << std::endl;
+
+    std::stringstream ss;
+    ss << cdt;
+
+    return ss.str();
+  };
+
+  const std::string ref_cdts = triangulate(0);
+
+  for (int i = 1; i < 20; ++i)
+  {
+    const std::string cdts = triangulate(i);
+    if (ref_cdts != cdts)
+      return 1;
+  }
+
+  return 0;
+}
diff --git a/Mesh_3/benchmark/Mesh_3/CMakeLists.txt b/Mesh_3/benchmark/Mesh_3/CMakeLists.txt
index aa4ede4ecf7..1987d458724 100644
--- a/Mesh_3/benchmark/Mesh_3/CMakeLists.txt
+++ b/Mesh_3/benchmark/Mesh_3/CMakeLists.txt
@@ -57,12 +57,14 @@ if ( CGAL_FOUND )
   if( CGAL_ACTIVATE_CONCURRENT_MESH_3 )
     add_definitions( -DCGAL_CONCURRENT_MESH_3 )
     find_package( TBB REQUIRED )
+    include(CGAL_TBB_support)
   else()
     option( LINK_WITH_TBB
       "Link with TBB anyway so we can use TBB timers for profiling"
       ON)
     if( LINK_WITH_TBB )
       find_package( TBB )
+      include(CGAL_TBB_support)
     endif( LINK_WITH_TBB )
   endif()
 
@@ -81,11 +83,11 @@ if ( CGAL_FOUND )
   if ( Boost_FOUND AND Boost_VERSION GREATER 103400 )
     # Compilable benchmark
     set (BENCHMARK_SOURCE_FILES "concurrency.cpp")
-    if(TBB_FOUND)
-      CGAL_target_use_TBB(concurrency)
-    endif()
     ADD_MSVC_PRECOMPILED_HEADER("StdAfx.h" "StdAfx.cpp" BENCHMARK_SOURCE_FILES)
     create_single_source_cgal_program( ${BENCHMARK_SOURCE_FILES} )
+    if(TARGET CGAL::TBB_support)
+      target_link_libraries(concurrency PUBLIC CGAL::TBB_support)
+    endif()
 
   else()
     message(STATUS "NOTICE: This program requires Boost >= 1.34.1, and will not be compiled.")
@@ -94,4 +96,3 @@ if ( CGAL_FOUND )
 else()
   message(STATUS "This program requires the CGAL library, and will not be compiled.")
 endif()
-
diff --git a/Mesh_3/examples/Mesh_3/CMakeLists.txt b/Mesh_3/examples/Mesh_3/CMakeLists.txt
index 7a259ab4037..851ce574dec 100644
--- a/Mesh_3/examples/Mesh_3/CMakeLists.txt
+++ b/Mesh_3/examples/Mesh_3/CMakeLists.txt
@@ -34,18 +34,21 @@ if ( CGAL_FOUND )
   if( CGAL_ACTIVATE_CONCURRENT_MESH_3 OR ENV{CGAL_ACTIVATE_CONCURRENT_MESH_3} )
     add_definitions( -DCGAL_CONCURRENT_MESH_3 )
     find_package( TBB REQUIRED )
+    include(CGAL_TBB_support)
   else( CGAL_ACTIVATE_CONCURRENT_MESH_3 OR ENV{CGAL_ACTIVATE_CONCURRENT_MESH_3} )
     option( LINK_WITH_TBB
       "Link with TBB anyway so we can use TBB timers for profiling"
       ON)
     if( LINK_WITH_TBB )
       find_package( TBB )
+      include(CGAL_TBB_support)
     endif( LINK_WITH_TBB )
   endif()
 
   # Use Eigen
   find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-  if (NOT EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (NOT TARGET CGAL::Eigen_support)
     message(STATUS "This project requires the Eigen library, and will not be compiled.")
     return()
   endif()
@@ -70,92 +73,91 @@ if ( CGAL_FOUND )
 
     # Compilable examples
     create_single_source_cgal_program( "mesh_hybrid_mesh_domain.cpp" )
-    CGAL_target_use_Eigen(mesh_hybrid_mesh_domain)
+    target_link_libraries(mesh_hybrid_mesh_domain PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_implicit_sphere.cpp" )
-    CGAL_target_use_Eigen(mesh_implicit_sphere)
+    target_link_libraries(mesh_implicit_sphere PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_implicit_sphere_variable_size.cpp" )
-    CGAL_target_use_Eigen(mesh_implicit_sphere_variable_size)
+    target_link_libraries(mesh_implicit_sphere_variable_size PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_two_implicit_spheres_with_balls.cpp" )
-    CGAL_target_use_Eigen(mesh_two_implicit_spheres_with_balls)
+    target_link_libraries(mesh_two_implicit_spheres_with_balls PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_implicit_domains_2.cpp" "implicit_functions.cpp" )
-    CGAL_target_use_Eigen(mesh_implicit_domains_2)
+    target_link_libraries(mesh_implicit_domains_2 PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_cubes_intersection.cpp" )
-    CGAL_target_use_Eigen(mesh_cubes_intersection)
+    target_link_libraries(mesh_cubes_intersection PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_cubes_intersection_with_features.cpp" )
-    CGAL_target_use_Eigen(mesh_cubes_intersection_with_features)
+    target_link_libraries(mesh_cubes_intersection_with_features PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_implicit_domains.cpp" "implicit_functions.cpp" )
-    CGAL_target_use_Eigen(mesh_implicit_domains)
+    target_link_libraries(mesh_implicit_domains PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_domain.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_domain)
+    target_link_libraries(mesh_polyhedral_domain PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_domain_sm.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_domain_sm)
+    target_link_libraries(mesh_polyhedral_domain_sm PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_domain_with_surface_inside.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_domain_with_surface_inside)
+    target_link_libraries(mesh_polyhedral_domain_with_surface_inside PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "remesh_polyhedral_surface.cpp" )
-    CGAL_target_use_Eigen(remesh_polyhedral_surface)
+    target_link_libraries(remesh_polyhedral_surface PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "remesh_polyhedral_surface_sm.cpp" )
-    CGAL_target_use_Eigen(remesh_polyhedral_surface_sm)
+    target_link_libraries(remesh_polyhedral_surface_sm PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_domain_with_features.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_domain_with_features)
+    target_link_libraries(mesh_polyhedral_domain_with_features PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_domain_with_features_sm.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_domain_with_features_sm)
+    target_link_libraries(mesh_polyhedral_domain_with_features_sm PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_domain_with_lipschitz_sizing.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_domain_with_lipschitz_sizing)
+    target_link_libraries(mesh_polyhedral_domain_with_lipschitz_sizing PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_complex.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_complex)
+    target_link_libraries(mesh_polyhedral_complex PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "mesh_polyhedral_complex_sm.cpp" )
-    CGAL_target_use_Eigen(mesh_polyhedral_complex_sm)
+    target_link_libraries(mesh_polyhedral_complex_sm PUBLIC CGAL::Eigen_support)
 
     if( WITH_CGAL_ImageIO )
       if( VTK_FOUND AND ("${VTK_VERSION_MAJOR}" GREATER "5" OR VTK_VERSION VERSION_GREATER 5) )
         add_executable ( mesh_3D_gray_vtk_image mesh_3D_gray_vtk_image.cpp )
-        CGAL_target_use_Eigen(mesh_3D_gray_vtk_image)
-        target_link_libraries(  mesh_3D_gray_vtk_image ${CGAL_LIBRARIES} ${CGAL_3RD_PARTY_LIBRARIES} ${VTK_LIBRARIES})
+        target_link_libraries(  mesh_3D_gray_vtk_image PUBLIC CGAL::Eigen_support ${CGAL_LIBRARIES} ${CGAL_3RD_PARTY_LIBRARIES} ${VTK_LIBRARIES})
         cgal_add_test( mesh_3D_gray_vtk_image )
         add_to_cached_list( CGAL_EXECUTABLE_TARGETS mesh_3D_gray_vtk_image )
       endif()
 
       create_single_source_cgal_program( "mesh_3D_gray_image.cpp" )
-      CGAL_target_use_Eigen(mesh_3D_gray_image)
+      target_link_libraries(mesh_3D_gray_image PUBLIC CGAL::Eigen_support)
 
       create_single_source_cgal_program( "mesh_3D_gray_image_multiple_values.cpp" )
-      CGAL_target_use_Eigen(mesh_3D_gray_image_multiple_values)
+      target_link_libraries(mesh_3D_gray_image_multiple_values PUBLIC CGAL::Eigen_support)
 
       create_single_source_cgal_program( "mesh_3D_image_with_features.cpp" )
-      CGAL_target_use_Eigen(mesh_3D_image_with_features)
+      target_link_libraries(mesh_3D_image_with_features PUBLIC CGAL::Eigen_support)
 
       if( CGAL_ImageIO_USE_ZLIB )
         create_single_source_cgal_program( "mesh_optimization_example.cpp" )
-        CGAL_target_use_Eigen(mesh_optimization_example)
+        target_link_libraries(mesh_optimization_example PUBLIC CGAL::Eigen_support)
 
         create_single_source_cgal_program( "mesh_optimization_lloyd_example.cpp" )
-        CGAL_target_use_Eigen(mesh_optimization_lloyd_example)
+        target_link_libraries(mesh_optimization_lloyd_example PUBLIC CGAL::Eigen_support)
 
         create_single_source_cgal_program( "mesh_3D_image.cpp" )
-        CGAL_target_use_Eigen(mesh_3D_image)
+        target_link_libraries(mesh_3D_image PUBLIC CGAL::Eigen_support)
 
         create_single_source_cgal_program( "mesh_3D_image_with_custom_initialization.cpp" )
-        CGAL_target_use_Eigen(mesh_3D_image_with_custom_initialization)
+        target_link_libraries(mesh_3D_image_with_custom_initialization PUBLIC CGAL::Eigen_support)
 
         create_single_source_cgal_program( "mesh_3D_image_variable_size.cpp" )
-        CGAL_target_use_Eigen(mesh_3D_image_variable_size)
+        target_link_libraries(mesh_3D_image_variable_size PUBLIC CGAL::Eigen_support)
       else()
         message( STATUS "NOTICE: The examples mesh_3D_image.cpp, mesh_3D_image_variable_size.cpp, mesh_optimization_example.cpp and mesh_optimization_lloyd_example.cpp need CGAL_ImageIO to be configured with ZLIB support, and will not be compiled." )
       endif()
@@ -167,28 +169,27 @@ if ( CGAL_FOUND )
 #    create_single_source_cgal_program( "mesh_polyhedral_surface_tolerance_region.cpp" )
 #    create_single_source_cgal_program( "mesh_polyhedral_edge_tolerance_region.cpp" )
 
-    if(CGAL_ACTIVATE_CONCURRENT_MESH_3 AND TBB_FOUND AND TARGET ${target})
+    if(CGAL_ACTIVATE_CONCURRENT_MESH_3 AND TARGET CGAL::TBB_support AND TARGET ${target})
       foreach(target
-        mesh_3D_image_with_features
-        mesh_3D_image
-        mesh_polyhedral_domain
-        mesh_3D_image_with_custom_initialization
-        mesh_two_implicit_spheres_with_balls
-        mesh_optimization_lloyd_example
-        mesh_optimization_example
-        mesh_implicit_sphere
-        mesh_polyhedral_complex_sm
-        mesh_implicit_sphere_variable_size
-        mesh_polyhedral_domain_sm
-        mesh_polyhedral_domain_with_lipschitz_sizing
-        mesh_polyhedral_complex
-        mesh_polyhedral_domain_with_features
-        mesh_3D_image_variable_size)
-        CGAL_target_use_TBB(${target})
+          mesh_3D_image_with_features
+          mesh_3D_image
+          mesh_polyhedral_domain
+          mesh_3D_image_with_custom_initialization
+          mesh_two_implicit_spheres_with_balls
+          mesh_optimization_lloyd_example
+          mesh_optimization_example
+          mesh_implicit_sphere
+          mesh_polyhedral_complex_sm
+          mesh_implicit_sphere_variable_size
+          mesh_polyhedral_domain_sm
+          mesh_polyhedral_domain_with_lipschitz_sizing
+          mesh_polyhedral_complex
+          mesh_polyhedral_domain_with_features
+          mesh_3D_image_variable_size)
+        target_link_libraries(${target} PUBLIC CGAL::TBB_support)
       endforeach()
     endif()
 
 else()
   message(STATUS "This program requires the CGAL library, and will not be compiled.")
 endif()
-
diff --git a/Mesh_3/include/CGAL/Compact_mesh_cell_base_3.h b/Mesh_3/include/CGAL/Compact_mesh_cell_base_3.h
index 9fe85b6765e..f1414264ca1 100644
--- a/Mesh_3/include/CGAL/Compact_mesh_cell_base_3.h
+++ b/Mesh_3/include/CGAL/Compact_mesh_cell_base_3.h
@@ -491,7 +491,7 @@ public:
 
   // For use by Compact_container.
   void * for_compact_container() const { return N[0].for_compact_container(); }
-  void * & for_compact_container()     { return N[0].for_compact_container(); }
+  void for_compact_container(void *p) { N[0].for_compact_container(p); }
 
   // TDS internal data access functions.
         TDS_data& tds_data()       { return _tds_data; }
diff --git a/Mesh_3/include/CGAL/IO/File_binary_mesh_3.h b/Mesh_3/include/CGAL/IO/File_binary_mesh_3.h
index b4ef55cc46b..52ac49d057b 100644
--- a/Mesh_3/include/CGAL/IO/File_binary_mesh_3.h
+++ b/Mesh_3/include/CGAL/IO/File_binary_mesh_3.h
@@ -13,7 +13,7 @@
 #ifndef CGAL_IO_FILE_BINARY_MESH_3_H
 #define CGAL_IO_FILE_BINARY_MESH_3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 #include <iostream>
diff --git a/Mesh_3/include/CGAL/IO/File_maya.h b/Mesh_3/include/CGAL/IO/File_maya.h
index 228e7648bf8..c482186b386 100644
--- a/Mesh_3/include/CGAL/IO/File_maya.h
+++ b/Mesh_3/include/CGAL/IO/File_maya.h
@@ -12,7 +12,7 @@
 #ifndef CGAL_IO_FILE_MAYA_H
 #define CGAL_IO_FILE_MAYA_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/Time_stamper.h>
 #include <CGAL/utility.h>
diff --git a/Mesh_3/include/CGAL/IO/File_medit.h b/Mesh_3/include/CGAL/IO/File_medit.h
index 81afaedf5dd..12ff8eb97f1 100644
--- a/Mesh_3/include/CGAL/IO/File_medit.h
+++ b/Mesh_3/include/CGAL/IO/File_medit.h
@@ -14,7 +14,7 @@
 #ifndef CGAL_IO_FILE_MEDIT_H
 #define CGAL_IO_FILE_MEDIT_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/Mesh_3/config.h>
 
@@ -754,7 +754,7 @@ output_to_medit(std::ostream& os,
 
   typedef typename Tr::Finite_vertices_iterator Finite_vertices_iterator;
   typedef typename Tr::Vertex_handle Vertex_handle;
-  typedef typename Tr::Weighted_point Weighted_point;
+  typedef typename Tr::Point Point; //can be weighted or not
 
   const Tr& tr = c3t3.triangulation();
 
@@ -783,7 +783,7 @@ output_to_medit(std::ostream& os,
        ++vit)
   {
     V[vit] = inum++;
-    Weighted_point p = tr.point(vit);
+    Point p = tr.point(vit);
     os << CGAL::to_double(p.x()) << ' '
        << CGAL::to_double(p.y()) << ' '
        << CGAL::to_double(p.z()) << ' '
diff --git a/Mesh_3/include/CGAL/IO/facets_in_complex_3_to_triangle_mesh.h b/Mesh_3/include/CGAL/IO/facets_in_complex_3_to_triangle_mesh.h
index 132df01c693..d69f445716f 100644
--- a/Mesh_3/include/CGAL/IO/facets_in_complex_3_to_triangle_mesh.h
+++ b/Mesh_3/include/CGAL/IO/facets_in_complex_3_to_triangle_mesh.h
@@ -14,7 +14,7 @@
 #ifndef CGAL_FACETS_IN_COMPLEX_3_TO_TRIANGLE_MESH_H
 #define CGAL_FACETS_IN_COMPLEX_3_TO_TRIANGLE_MESH_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/array.h>
 #include <CGAL/boost/graph/Euler_operations.h>
diff --git a/Mesh_3/include/CGAL/Mesh_3/Has_features.h b/Mesh_3/include/CGAL/Mesh_3/Has_features.h
index 2eb7f6844fa..94d9b02de4b 100644
--- a/Mesh_3/include/CGAL/Mesh_3/Has_features.h
+++ b/Mesh_3/include/CGAL/Mesh_3/Has_features.h
@@ -13,7 +13,7 @@
 #ifndef CGAL_MESH_3_HAS_FEATURES_H
 #define CGAL_MESH_3_HAS_FEATURES_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 #include <boost/mpl/has_xxx.hpp>
diff --git a/Mesh_3/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h b/Mesh_3/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h
index 02b31a987b9..af999cd1bc9 100644
--- a/Mesh_3/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h
+++ b/Mesh_3/include/CGAL/Mesh_3/Mesh_complex_3_in_triangulation_3_base.h
@@ -18,7 +18,7 @@
 #ifndef CGAL_MESH_3_MESH_COMPLEX_3_IN_TRIANGULATION_3_BASE_H
 #define CGAL_MESH_3_MESH_COMPLEX_3_IN_TRIANGULATION_3_BASE_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/disable_warnings.h>
 
diff --git a/Mesh_3/include/CGAL/Mesh_3/Mesh_surface_cell_base_3.h b/Mesh_3/include/CGAL/Mesh_3/Mesh_surface_cell_base_3.h
index 4bd39365f22..f4b279a0fdc 100644
--- a/Mesh_3/include/CGAL/Mesh_3/Mesh_surface_cell_base_3.h
+++ b/Mesh_3/include/CGAL/Mesh_3/Mesh_surface_cell_base_3.h
@@ -18,7 +18,7 @@
 #ifndef CGAL_MESH_3_MESH_SURFACE_CELL_BASE_3_H
 #define CGAL_MESH_3_MESH_SURFACE_CELL_BASE_3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 #include <CGAL/Mesh_3/config.h>
diff --git a/Mesh_3/include/CGAL/Mesh_3/config.h b/Mesh_3/include/CGAL/Mesh_3/config.h
index 07e7c765993..ccb05647ef5 100644
--- a/Mesh_3/include/CGAL/Mesh_3/config.h
+++ b/Mesh_3/include/CGAL/Mesh_3/config.h
@@ -12,7 +12,7 @@
 #ifndef CGAL_MESH_3_CONFIG_H
 #define CGAL_MESH_3_CONFIG_H 1
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 #include <CGAL/config.h>
diff --git a/Mesh_3/include/CGAL/Mesh_3/io_signature.h b/Mesh_3/include/CGAL/Mesh_3/io_signature.h
index 286d5e5e3ac..d871b8ffe7d 100644
--- a/Mesh_3/include/CGAL/Mesh_3/io_signature.h
+++ b/Mesh_3/include/CGAL/Mesh_3/io_signature.h
@@ -13,7 +13,7 @@
 #ifndef CGAL_MESH_3_IO_SIGNATURE_H
 #define CGAL_MESH_3_IO_SIGNATURE_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #define CGAL_MESH_3_IO_H // the old include macro, tested by other files
 
diff --git a/Mesh_3/include/CGAL/Mesh_3/tet_soup_to_c3t3.h b/Mesh_3/include/CGAL/Mesh_3/tet_soup_to_c3t3.h
index c5cd5256df3..632d87a83d8 100644
--- a/Mesh_3/include/CGAL/Mesh_3/tet_soup_to_c3t3.h
+++ b/Mesh_3/include/CGAL/Mesh_3/tet_soup_to_c3t3.h
@@ -17,18 +17,32 @@
 #ifndef CGAL_MESH_3_TET_SOUP_TO_C3T3_H
 #define CGAL_MESH_3_TET_SOUP_TO_C3T3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/disable_warnings.h>
 #include <CGAL/assertions.h>
 #include <CGAL/IO/File_medit.h>
 
-#include <boost/array.hpp>
+#include <array>
+#include <vector>
+#include <utility>
+#include <map>
 #include <boost/unordered_map.hpp>
 
 
 namespace CGAL
 {
+
+template<typename Vh>
+std::array<Vh, 3> make_ordered_vertex_array(const Vh vh0, const Vh vh1, const Vh vh2)
+{
+  std::array<Vh, 3> ft = { {vh0, vh1, vh2} };
+  if (ft[1] < ft[0]) std::swap(ft[0], ft[1]);
+  if (ft[2] < ft[1]) std::swap(ft[1], ft[2]);
+  if (ft[1] < ft[0]) std::swap(ft[0], ft[1]);
+  return ft;
+}
+
 template<class Tr>
 void build_vertices(Tr& tr,
                     const std::vector<typename Tr::Point>& points,
@@ -49,22 +63,22 @@ void build_vertices(Tr& tr,
 }
 
 template<class Tr>
-void add_facet_to_incident_cells_map(const typename Tr::Cell_handle c, int i,
-                                     boost::unordered_map<std::set<typename Tr::Vertex_handle>,
-                                     std::vector<std::pair<typename Tr::Cell_handle, int> > >& incident_cells_map)
+bool add_facet_to_incident_cells_map(const typename Tr::Cell_handle c, int i,
+    boost::unordered_map<std::array<typename Tr::Vertex_handle, 3>,
+                         std::vector<std::pair<typename Tr::Cell_handle, int> > >& incident_cells_map,
+    const bool verbose)
 {
   typedef typename Tr::Vertex_handle                                Vertex_handle;
   typedef typename Tr::Cell_handle                                  Cell_handle;
-  typedef std::set<Vertex_handle>                                   Facet;
+  typedef std::array<Vertex_handle, 3>                              Facet_vvv;
   typedef std::pair<Cell_handle, int>                               Incident_cell;
-  typedef boost::unordered_map<Facet, std::vector<Incident_cell> >  Incident_cells_map;
+  typedef boost::unordered_map<Facet_vvv, std::vector<Incident_cell> > Incident_cells_map;
 
   // the opposite vertex of f in c is i
-  Facet f;
-  f.insert(c->vertex((i + 1) % 4));
-  f.insert(c->vertex((i + 2) % 4));
-  f.insert(c->vertex((i + 3) % 4));
-  CGAL_precondition(f.size() == 3);
+  Facet_vvv f = make_ordered_vertex_array(c->vertex((i + 1) % 4),
+                                          c->vertex((i + 2) % 4),
+                                          c->vertex((i + 3) % 4));
+  CGAL_precondition(f[0] != f[1] && f[1] != f[2]);
 
   Incident_cell e = std::make_pair(c, i);
   std::vector<Incident_cell> vec;
@@ -74,20 +88,27 @@ void add_facet_to_incident_cells_map(const typename Tr::Cell_handle c, int i,
   if(!is_insert_successful.second) // the entry already exists in the map
   {
     // a facet must have exactly two incident cells
-    CGAL_assertion(is_insert_successful.first->second.size() == 1);
+    if (is_insert_successful.first->second.size() != 1)
+    {
+      if(verbose)
+        std::cout << "Error in add_facet_to_incident_cells_map" << std::endl;
+      return false;
+    }
     is_insert_successful.first->second.push_back(e);
   }
+  return true;
 }
 
 template<class Tr>
-void build_finite_cells(Tr& tr,
-                        const std::vector<boost::array<int,5> >& finite_cells,
-                        const std::vector<typename Tr::Vertex_handle>& vertex_handle_vector,
-                        boost::unordered_map<std::set<typename Tr::Vertex_handle>,
+bool build_finite_cells(Tr& tr,
+    const std::vector<std::array<int,5> >& finite_cells,
+    const std::vector<typename Tr::Vertex_handle>& vertex_handle_vector,
+    boost::unordered_map<std::array<typename Tr::Vertex_handle, 3>,
                         std::vector<std::pair<typename Tr::Cell_handle, int> > >& incident_cells_map,
-                        const std::map<boost::array<int,3>, int>& border_facets)
+    const std::map<std::array<int,3>, int>& border_facets,
+    const bool verbose)
 {
-  typedef boost::array<int, 5>              Tet_with_ref; // 4 ids + 1 reference
+  typedef std::array<int, 5>              Tet_with_ref; // 4 ids + 1 reference
 
   typedef typename Tr::Vertex_handle                            Vertex_handle;
   typedef typename Tr::Cell_handle                              Cell_handle;
@@ -101,7 +122,7 @@ void build_finite_cells(Tr& tr,
   for(std::size_t i=0; i<finite_cells.size(); ++i)
   {
     const Tet_with_ref& tet = finite_cells[i];
-    boost::array<Vertex_handle, 4> vs;
+    std::array<Vertex_handle, 4> vs;
 
     for(int j=0; j<4; ++j)
     {
@@ -118,9 +139,8 @@ void build_finite_cells(Tr& tr,
                      == POSITIVE);
 
     Cell_handle c = tr.tds().create_cell(vs[0], vs[1], vs[2], vs[3]);
-    c->info() = tet[4]; // the cell's info keeps the reference of the tetrahedron
+    c->set_subdomain_index(tet[4]); // the cell's info keeps the reference of the tetrahedron
 
-    CGAL_precondition(tet[4] > 0);
     // assign cells to vertices
     for(int j=0; j<4; ++j)
     {
@@ -131,17 +151,18 @@ void build_finite_cells(Tr& tr,
     // build the map used for adjacency later
     for(int j=0; j<4; ++j)
     {
-      add_facet_to_incident_cells_map<Tr>(c, j, incident_cells_map);
+      if(!add_facet_to_incident_cells_map<Tr>(c, j, incident_cells_map, verbose))
+        return false;
       if(border_facets.size() != 0)
       {
-        boost::array<int,3> facet;
+        std::array<int,3> facet;
         facet[0]=tet[(j+1) % 4];
         facet[1]=tet[(j+2) % 4];
         facet[2]=tet[(j+3) % 4];
         //find the circular permutation that puts the smallest index in the first place.
         int n0 = (std::min)((std::min)(facet[0], facet[1]), facet[2]);
         int k=0;
-        boost::array<int,3> f;
+        std::array<int,3> f;
         do
         {
           f[0]=facet[(0+k)%3];
@@ -150,7 +171,7 @@ void build_finite_cells(Tr& tr,
           ++k;
         } while(f[0] != n0);
 
-        typename std::map<boost::array<int,3>, int>::const_iterator it = border_facets.find(f);
+        typename std::map<std::array<int,3>, int>::const_iterator it = border_facets.find(f);
         if(it != border_facets.end())
         {
           c->set_surface_patch_index(j, it->second);
@@ -170,34 +191,38 @@ void build_finite_cells(Tr& tr,
       }
     }
   }
+  return true;
 }
 
 template<class Tr>
-void add_infinite_facets_to_incident_cells_map(typename Tr::Cell_handle c,
-                                               int inf_vert_pos,
-                                               std::map<std::set<typename Tr::Vertex_handle>,
-                                               std::vector<std::pair<typename Tr::Cell_handle,
-                                               int> > >& incident_cells_map)
+bool add_infinite_facets_to_incident_cells_map(typename Tr::Cell_handle c,
+     int inf_vert_pos,
+     boost::unordered_map<std::array<typename Tr::Vertex_handle, 3>,
+                          std::vector<std::pair<typename Tr::Cell_handle, int> > >& incident_cells_map,
+     const bool verbose)
 {
   int l = (inf_vert_pos + 1) % 4;
-  add_facet_to_incident_cells_map<Tr>(c, l, incident_cells_map);
+  bool b1 = add_facet_to_incident_cells_map<Tr>(c, l, incident_cells_map, verbose);
   l = (inf_vert_pos + 2) % 4;
-  add_facet_to_incident_cells_map<Tr>(c, l, incident_cells_map);
+  bool b2 = add_facet_to_incident_cells_map<Tr>(c, l, incident_cells_map, verbose);
   l = (inf_vert_pos + 3) % 4;
-  add_facet_to_incident_cells_map<Tr>(c, l, incident_cells_map);
+  bool b3 = add_facet_to_incident_cells_map<Tr>(c, l, incident_cells_map, verbose);
+  return b1 && b2 && b3;
 }
 
 template<class Tr>
-void build_infinite_cells(Tr& tr,
-                          boost::unordered_map<std::set<typename Tr::Vertex_handle>,
-                          std::vector<std::pair<typename Tr::Cell_handle,
-                          int> > >& incident_cells_map)
+bool build_infinite_cells(Tr& tr,
+  boost::unordered_map<std::array<typename Tr::Vertex_handle, 3>,
+                       std::vector<std::pair<typename Tr::Cell_handle, int> > >& incident_cells_map,
+  const bool verbose)
 {
   typedef typename Tr::Vertex_handle                               Vertex_handle;
   typedef typename Tr::Cell_handle                                 Cell_handle;
-  typedef std::set<Vertex_handle>                                  Facet;
+  typedef std::array<Vertex_handle, 3>                             Facet_vvv;
   typedef std::pair<Cell_handle, int>                              Incident_cell;
-  typedef boost::unordered_map<Facet, std::vector<Incident_cell> > Incident_cells_map;
+  typedef boost::unordered_map<Facet_vvv, std::vector<Incident_cell> > Incident_cells_map;
+
+  std::vector<Cell_handle> infinite_cells;
 
   // check the incident cells map for facets who only have one incident cell
   // and build the infinite cell on the opposite side
@@ -214,41 +239,67 @@ void build_infinite_cells(Tr& tr,
 
     Cell_handle opp_c;
     // the infinite cell that we are creating needs to be well oriented...
-    int inf_vert_position_in_opp_c = 0;
     if(i == 0 || i == 2)
       opp_c = tr.tds().create_cell(tr.infinite_vertex(),
-                                   c->vertex((i+1)%4),
-                                   c->vertex((i+2)%4),
-                                   c->vertex((i+3)%4));
+                                   c->vertex((i + 2) % 4),
+                                   c->vertex((i + 1) % 4),
+                                   c->vertex((i + 3) % 4));
     else
       opp_c = tr.tds().create_cell(tr.infinite_vertex(),
-                                   c->vertex((i+1)%4),
-                                   c->vertex((i+3)%4),
-                                   c->vertex((i+2)%4));
+                                   c->vertex((i + 3) % 4),
+                                   c->vertex((i + 1) % 4),
+                                   c->vertex((i + 2) % 4));
+
+    infinite_cells.push_back(opp_c);
 
     // set the infinite_vertex's incident cell
     if(tr.infinite_vertex()->cell() == Cell_handle())
       tr.infinite_vertex()->set_cell(opp_c);
 
-    // add the facets to the incident cells map
-
     // the only finite facet
-    it->second.push_back(std::make_pair(opp_c, inf_vert_position_in_opp_c));
+    it->second.push_back(std::make_pair(opp_c, 0));
     CGAL_assertion(it->second.size() == 2);
   }
+
+#ifdef CGAL_TET_SOUP_TO_C3T3_DEBUG
+  for (auto icit : incident_cells_map)
+    CGAL_assertion(icit.second.size() == 2);
+
+  std::map<Facet_vvv, int> facets;
+  for (const Cell_handle c : infinite_cells)
+  {
+    for (int i = 1; i < 4; ++i)
+    {
+      std::array<Vertex_handle, 3> vs = make_ordered_vertex_array(c->vertex((i + 1) % 4),
+        c->vertex((i + 2) % 4),
+        c->vertex((i + 3) % 4));
+      if (facets.find(vs) == facets.end())
+        facets.insert(std::make_pair(vs, 1));
+      else
+        facets[vs]++;
+    }
+  }
+  for (auto fp : facets)
+    CGAL_assertion(fp.second == 2);
+#endif
+
+  // add the facets to the incident cells map
+  for (const Cell_handle c : infinite_cells)
+    if(!add_infinite_facets_to_incident_cells_map<Tr>(c, 0, incident_cells_map, verbose))
+      return false;
+
+  return true;
 }
 
 template<class Tr>
 bool assign_neighbors(Tr& tr,
-                      const boost::unordered_map<std::set<typename Tr::Vertex_handle>,
-                      std::vector<std::pair<typename Tr::Cell_handle,
-                      int> > >& incident_cells_map)
+  const boost::unordered_map<std::array<typename Tr::Vertex_handle, 3>,
+                             std::vector<std::pair<typename Tr::Cell_handle, int> > >& incident_cells_map)
 {
-  typedef typename Tr::Vertex_handle                                 Vertex_handle;
   typedef typename Tr::Cell_handle                                   Cell_handle;
-  typedef std::set<Vertex_handle>                                    Facet;
   typedef std::pair<Cell_handle, int>                                Incident_cell;
-  typedef boost::unordered_map<Facet, std::vector<Incident_cell> >   Incident_cells_map;
+  typedef boost::unordered_map<std::array<typename Tr::Vertex_handle, 3>,
+                               std::vector<Incident_cell> >          Incident_cells_map;
 
   typename Incident_cells_map::const_iterator icit = incident_cells_map.begin();
   for(; icit!=incident_cells_map.end(); ++icit)
@@ -270,19 +321,23 @@ bool assign_neighbors(Tr& tr,
 template<class Tr, bool c3t3_loader_failed>
 bool build_triangulation(Tr& tr,
                          const std::vector<typename Tr::Point>& points,
-                         const std::vector<boost::array<int,5> >& finite_cells,
-                         const std::map<boost::array<int,3>, int>& border_facets)
+                         const std::vector<std::array<int,5> >& finite_cells,
+                         const std::map<std::array<int,3>, int>& border_facets,
+                         std::vector<typename Tr::Vertex_handle>& vertex_handle_vector,
+                         const bool verbose = false)
 {
   typedef typename Tr::Vertex_handle            Vertex_handle;
   typedef typename Tr::Cell_handle              Cell_handle;
-  typedef std::set<Vertex_handle>               Facet;
+  typedef std::array<Vertex_handle, 3>          Facet_vvv;
 
   // associate to a face the two (at most) incident tets and the id of the face in the cell
   typedef std::pair<Cell_handle, int>                   Incident_cell;
-  typedef boost::unordered_map<Facet, std::vector<Incident_cell> >  Incident_cells_map;
+  typedef boost::unordered_map<Facet_vvv, std::vector<Incident_cell> >  Incident_cells_map;
 
   Incident_cells_map incident_cells_map;
-  std::vector<Vertex_handle> vertex_handle_vector(points.size() + 1); // id to vertex_handle
+  vertex_handle_vector.resize(points.size() + 1); // id to vertex_handle
+                                        //index 0 is for infinite vertex
+                                        // 1 to n for points in `points`
 
   CGAL_precondition(!points.empty());
 
@@ -298,22 +353,29 @@ bool build_triangulation(Tr& tr,
   {
     vh->set_dimension(-1);
   }
-  if(!finite_cells.empty())
+  if (!finite_cells.empty())
   {
-    build_finite_cells<Tr>(tr, finite_cells, vertex_handle_vector, incident_cells_map, border_facets);
-    build_infinite_cells<Tr>(tr, incident_cells_map);
-    tr.tds().set_dimension(3);
-    if(!assign_neighbors<Tr>(tr, incident_cells_map))
+    if(!build_finite_cells<Tr>(tr, finite_cells, vertex_handle_vector, incident_cells_map,
+                           border_facets, verbose))
       return false;
-    std::cout << "built triangulation : " << std::endl;
-    std::cout << tr.number_of_cells() << " cells" << std::endl;
+    if(!build_infinite_cells<Tr>(tr, incident_cells_map, verbose))
+      return false;
+    tr.tds().set_dimension(3);
+    if (!assign_neighbors<Tr>(tr, incident_cells_map))
+      return false;
+    if (verbose)
+    {
+      std::cout << "built triangulation : " << std::endl;
+      std::cout << tr.number_of_cells() << " cells" << std::endl;
+    }
   }
-  std::cout << tr.number_of_vertices() << " vertices" << std::endl;
+  if(verbose)
+    std::cout << tr.number_of_vertices() << " vertices" << std::endl;
 
   if(c3t3_loader_failed)
     return true;
   else
-    return tr.is_valid(true);
+    return tr.tds().is_valid();
 }
 
 template<class Tr, bool c3t3_loader_failed>
@@ -322,8 +384,8 @@ bool build_triangulation_from_file(std::istream& is,
 {
   typedef typename Tr::Point                                  Point_3;
 
-  typedef boost::array<int, 3> Facet; // 3 = id
-  typedef boost::array<int, 5> Tet_with_ref; // first 4 = id, fifth = reference
+  typedef std::array<int, 3> Facet; // 3 = id
+  typedef std::array<int, 5> Tet_with_ref; // first 4 = id, fifth = reference
 
   std::vector<Tet_with_ref> finite_cells;
   std::vector<Point_3> points;
@@ -404,7 +466,9 @@ bool build_triangulation_from_file(std::istream& is,
   if(finite_cells.empty())
     return false;
 
-  bool is_well_built = build_triangulation<Tr, c3t3_loader_failed>(tr, points, finite_cells, border_facets);
+  std::vector<typename Tr::Vertex_handle> vertices(points.size() + 1);
+  bool is_well_built = build_triangulation<Tr, c3t3_loader_failed>(tr,
+    points, finite_cells, border_facets, vertices);
   return is_well_built;
 }
 
diff --git a/Mesh_3/include/CGAL/Mesh_3/utilities.h b/Mesh_3/include/CGAL/Mesh_3/utilities.h
index 4d73f43de53..5e49f7a617e 100644
--- a/Mesh_3/include/CGAL/Mesh_3/utilities.h
+++ b/Mesh_3/include/CGAL/Mesh_3/utilities.h
@@ -17,7 +17,7 @@
 #ifndef CGAL_MESH_3_UTILITIES_H
 #define CGAL_MESH_3_UTILITIES_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/Has_timestamp.h>
 #include <iterator>
diff --git a/Mesh_3/include/CGAL/Mesh_cell_base_3.h b/Mesh_3/include/CGAL/Mesh_cell_base_3.h
index 5c719d22fe6..2babd0cc5db 100644
--- a/Mesh_3/include/CGAL/Mesh_cell_base_3.h
+++ b/Mesh_3/include/CGAL/Mesh_cell_base_3.h
@@ -15,7 +15,7 @@
 #ifndef CGAL_MESH_CELL_BASE_3_H
 #define CGAL_MESH_CELL_BASE_3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 // #define CGAL_DEPRECATED_HEADER "<CGAL/Mesh_cell_base_3.h>"
diff --git a/Mesh_3/include/CGAL/Mesh_complex_3_in_triangulation_3.h b/Mesh_3/include/CGAL/Mesh_complex_3_in_triangulation_3.h
index 954478ccee7..8fb53524d81 100644
--- a/Mesh_3/include/CGAL/Mesh_complex_3_in_triangulation_3.h
+++ b/Mesh_3/include/CGAL/Mesh_complex_3_in_triangulation_3.h
@@ -18,7 +18,7 @@
 #ifndef CGAL_MESH_COMPLEX_3_IN_TRIANGULATION_3_H
 #define CGAL_MESH_COMPLEX_3_IN_TRIANGULATION_3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/disable_warnings.h>
 #include <CGAL/iterator.h>
diff --git a/Mesh_3/include/CGAL/Mesh_vertex_base_3.h b/Mesh_3/include/CGAL/Mesh_vertex_base_3.h
index 9ad67147d1b..aeb3411a1e1 100644
--- a/Mesh_3/include/CGAL/Mesh_vertex_base_3.h
+++ b/Mesh_3/include/CGAL/Mesh_vertex_base_3.h
@@ -20,7 +20,7 @@
 #ifndef CGAL_COMPACT_MESH_VERTEX_BASE_3_H
 #define CGAL_COMPACT_MESH_VERTEX_BASE_3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 #include <CGAL/Regular_triangulation_vertex_base_3.h>
diff --git a/Mesh_3/include/CGAL/internal/Mesh_3/Boundary_of_subdomain_of_complex_3_in_triangulation_3_to_off.h b/Mesh_3/include/CGAL/internal/Mesh_3/Boundary_of_subdomain_of_complex_3_in_triangulation_3_to_off.h
index 08ecbdb070a..b08974e545e 100644
--- a/Mesh_3/include/CGAL/internal/Mesh_3/Boundary_of_subdomain_of_complex_3_in_triangulation_3_to_off.h
+++ b/Mesh_3/include/CGAL/internal/Mesh_3/Boundary_of_subdomain_of_complex_3_in_triangulation_3_to_off.h
@@ -12,7 +12,7 @@
 #ifndef CGAL_INTERNAL_MESH_3_BOUNDARY_OF_SUDDOMAIN_OF_COMPLEX_3_IN_TRIANGULATION_3_TO_OFF_H
 #define CGAL_INTERNAL_MESH_3_BOUNDARY_OF_SUDDOMAIN_OF_COMPLEX_3_IN_TRIANGULATION_3_TO_OFF_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/IO/facets_in_complex_3_to_triangle_mesh.h>
 
diff --git a/Mesh_3/include/CGAL/internal/Mesh_3/get_index.h b/Mesh_3/include/CGAL/internal/Mesh_3/get_index.h
index b84f4639b51..1bbf2f971aa 100644
--- a/Mesh_3/include/CGAL/internal/Mesh_3/get_index.h
+++ b/Mesh_3/include/CGAL/internal/Mesh_3/get_index.h
@@ -17,7 +17,7 @@
 #ifndef CGAL_INTERNAL_MESH_3_GET_INDEX_3_H
 #define CGAL_INTERNAL_MESH_3_GET_INDEX_3_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 #include <CGAL/internal/Mesh_3/indices_management.h>
 
diff --git a/Mesh_3/include/CGAL/internal/Mesh_3/indices_management.h b/Mesh_3/include/CGAL/internal/Mesh_3/indices_management.h
index 6f637bebb48..62bde6e2135 100644
--- a/Mesh_3/include/CGAL/internal/Mesh_3/indices_management.h
+++ b/Mesh_3/include/CGAL/internal/Mesh_3/indices_management.h
@@ -18,7 +18,7 @@
 #ifndef CGAL_INTERNAL_MESH_3_INDICES_MANAGEMENT_H
 #define CGAL_INTERNAL_MESH_3_INDICES_MANAGEMENT_H
 
-#include <CGAL/license/Mesh_3.h>
+#include <CGAL/license/Triangulation_3.h>
 
 
 #include <boost/type_traits/is_same.hpp>
diff --git a/Mesh_3/test/Mesh_3/CMakeLists.txt b/Mesh_3/test/Mesh_3/CMakeLists.txt
index ee17ea5e154..d731e12d4e4 100644
--- a/Mesh_3/test/Mesh_3/CMakeLists.txt
+++ b/Mesh_3/test/Mesh_3/CMakeLists.txt
@@ -16,10 +16,12 @@ if ( CGAL_FOUND )
   include( ${CGAL_USE_FILE} )
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
 
   # Use Eigen
   find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-  if (NOT EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (NOT TARGET CGAL::Eigen_support)
     message(STATUS "This project requires the Eigen library, and will not be compiled.")
     return()
   endif()
@@ -91,32 +93,33 @@ if ( CGAL_FOUND )
       test_mesh_polyhedral_domain_with_features_deprecated
       test_meshing_with_one_step.cpp)
     if(TARGET ${target})
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endif()
   endforeach()
 
-  foreach(target
-      test_meshing_verbose
-      test_meshing_polyhedron_with_features
-      test_meshing_utilities.h
-      test_meshing_implicit_function
-      test_meshing_3D_image
-      test_meshing_3D_gray_image
-      test_meshing_unit_tetrahedron
-      test_meshing_polyhedron
-      test_meshing_polyhedral_complex
-      test_mesh_capsule_var_distance_bound
-      test_mesh_3_issue_1554
-      test_mesh_polyhedral_domain_with_features_deprecated
-      )
-    if(TBB_FOUND AND TARGET ${target})
-      CGAL_target_use_TBB(${target})
-    endif()
-  endforeach()
+  if(TARGET CGAL::TBB_support)
+    foreach(target
+        test_meshing_verbose
+        test_meshing_polyhedron_with_features
+        test_meshing_utilities.h
+        test_meshing_implicit_function
+        test_meshing_3D_image
+        test_meshing_3D_gray_image
+        test_meshing_unit_tetrahedron
+        test_meshing_polyhedron
+        test_meshing_polyhedral_complex
+        test_mesh_capsule_var_distance_bound
+        test_mesh_3_issue_1554
+        test_mesh_polyhedral_domain_with_features_deprecated
+        )
+      if(TARGET ${target})
+        target_link_libraries(${target} PUBLIC CGAL::TBB_support)
+      endif()
+    endforeach()
+  endif()
 
 else()
 
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Mesh_3/test/Mesh_3/test_c3t3_into_facegraph.cpp b/Mesh_3/test/Mesh_3/test_c3t3_into_facegraph.cpp
index 124cb0f75aa..6df89caf971 100644
--- a/Mesh_3/test/Mesh_3/test_c3t3_into_facegraph.cpp
+++ b/Mesh_3/test/Mesh_3/test_c3t3_into_facegraph.cpp
@@ -49,8 +49,8 @@ int main (int argc, char** argv){
          cit != c3t3.triangulation().finite_cells_end();
          ++cit)
     {
-      CGAL_assertion(cit->info() >= 0);
-      c3t3.add_to_complex(cit, cit->info());
+      CGAL_assertion(cit->subdomain_index() >= 0);
+      c3t3.add_to_complex(cit, cit->subdomain_index());
       for(int i=0; i < 4; ++i)
       {
         if(cit->surface_patch_index(i)>0)
diff --git a/Nef_3/include/CGAL/Nef_nary_intersection_3.h b/Nef_3/include/CGAL/Nef_nary_intersection_3.h
index 70fc5791fae..5178705dc2f 100644
--- a/Nef_3/include/CGAL/Nef_nary_intersection_3.h
+++ b/Nef_3/include/CGAL/Nef_nary_intersection_3.h
@@ -52,7 +52,8 @@ class Nef_nary_intersection_3 {
   }
 
   Polyhedron get_intersection() {
-
+    if (queue.empty())
+      return empty;
     while(queue.size() > 1)
       intersect();
     inserted = 0;
diff --git a/Nef_3/include/CGAL/Nef_nary_union_3.h b/Nef_3/include/CGAL/Nef_nary_union_3.h
index ecbbae2db59..c8663bb911b 100644
--- a/Nef_3/include/CGAL/Nef_nary_union_3.h
+++ b/Nef_3/include/CGAL/Nef_nary_union_3.h
@@ -52,7 +52,8 @@ class Nef_nary_union_3 {
   }
 
   Polyhedron get_union() {
-
+    if (queue.empty())
+      return empty;
     while(queue.size() > 1)
       unite();
     inserted = 0;
diff --git a/NewKernel_d/include/CGAL/Epick_d.h b/NewKernel_d/include/CGAL/Epick_d.h
index 54b6633ebec..39575dd034a 100644
--- a/NewKernel_d/include/CGAL/Epick_d.h
+++ b/NewKernel_d/include/CGAL/Epick_d.h
@@ -40,7 +40,12 @@ struct Epick_d_help1
 };
 #undef CGAL_BASE
 #define CGAL_BASE \
-  Cartesian_static_filters<Dim,Epick_d_help1<Dim>,Epick_d_help2<Dim> >
+  Cartesian_filter_K< \
+    Epick_d_help1<Dim>, \
+    Cartesian_base_d<Interval_nt_advanced, Dim>, \
+    Cartesian_base_d<internal::Exact_ring_selector<double>::Type, Dim>, \
+    typename Functors_without_division<Dim>::type \
+  >
 template<class Dim>
 struct Epick_d_help2
 : CGAL_BASE
@@ -49,10 +54,21 @@ struct Epick_d_help2
   constexpr Epick_d_help2(int d):CGAL_BASE(d){}
 };
 #undef CGAL_BASE
+#define CGAL_BASE \
+  Cartesian_static_filters<Dim,Epick_d_help2<Dim>,Epick_d_help3<Dim> >
+
+template<class Dim>
+struct Epick_d_help3
+: CGAL_BASE
+{
+  constexpr Epick_d_help3(){}
+  constexpr Epick_d_help3(int d):CGAL_BASE(d){}
+};
+#undef CGAL_BASE
 #define CGAL_BASE \
   Kernel_d_interface< \
     Cartesian_wrap< \
-      Epick_d_help2<Dim>, \
+      Epick_d_help3<Dim>, \
       Epick_d<Dim> > >
 template<class Dim>
 struct Epick_d
diff --git a/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_LA_functors.h b/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_LA_functors.h
index 1bfc92a88c8..a379cee7ed9 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_LA_functors.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_LA_functors.h
@@ -58,7 +58,7 @@ template<class R_,class Zero_> struct Construct_LA_vector
         }
         template<class...U>
         typename std::enable_if<Constructible_from_each<RT,U...>::value &&
-                std::is_same<Dimension_tag<sizeof...(U)>, Dimension>::value,
+                std::is_same<Dimension_tag<int(sizeof...(U))>, Dimension>::value,
           result_type>::type
         operator()(U&&...u)const{
                 return typename Constructor::Values()(std::forward<U>(u)...);
@@ -66,7 +66,7 @@ template<class R_,class Zero_> struct Construct_LA_vector
         //template<class...U,class=typename std::enable_if<Constructible_from_each<RT,U...>::value>::type,class=typename std::enable_if<(sizeof...(U)==static_dim+1)>::type,class=void>
         template<class...U>
         typename std::enable_if<Constructible_from_each<RT,U...>::value &&
-                std::is_same<Dimension_tag<sizeof...(U)-1>, Dimension>::value,
+                std::is_same<Dimension_tag<int(sizeof...(U)-1)>, Dimension>::value,
           result_type>::type
         operator()(U&&...u)const{
                 return Apply_to_last_then_rest()(typename Constructor::Values_divide(),std::forward<U>(u)...);
diff --git a/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_filter_K.h b/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_filter_K.h
index 3496330a7ac..ed164e844da 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_filter_K.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/Cartesian_filter_K.h
@@ -20,23 +20,49 @@
 
 namespace CGAL {
 
-template < typename Base_, typename AK_, typename EK_ >
-struct Cartesian_filter_K : public Base_,
-  private Store_kernel<AK_>, private Store_kernel2<EK_>
+  // It would be nicer to write the table in the other direction: Orientation_of_points_tag is good up to 6, Side_of_oriented_sphere_tag up to 5, etc.
+template<class> struct Functors_without_division { typedef typeset<> type; };
+template<> struct Functors_without_division<Dimension_tag<1> > {
+  typedef typeset<Orientation_of_points_tag, Side_of_oriented_sphere_tag> type;
+};
+template<> struct Functors_without_division<Dimension_tag<2> > {
+  typedef typeset<Orientation_of_points_tag, Side_of_oriented_sphere_tag> type;
+};
+template<> struct Functors_without_division<Dimension_tag<3> > {
+  typedef typeset<Orientation_of_points_tag, Side_of_oriented_sphere_tag> type;
+};
+template<> struct Functors_without_division<Dimension_tag<4> > {
+  typedef typeset<Orientation_of_points_tag, Side_of_oriented_sphere_tag> type;
+};
+template<> struct Functors_without_division<Dimension_tag<5> > {
+  typedef typeset<Orientation_of_points_tag, Side_of_oriented_sphere_tag> type;
+};
+template<> struct Functors_without_division<Dimension_tag<6> > {
+  typedef typeset<Orientation_of_points_tag, Side_of_oriented_sphere_tag> type;
+};
+
+// FIXME:
+// - Is_exact (which should be renamed to Uses_no_arithmetic) predicates should not be filtered
+// - Functors_without_division should be defined near/in the actual functors
+
+template < typename Base_, typename AK_, typename EK_, typename Pred_list = typeset_all >
+struct Cartesian_filter_K : public Base_
 {
+    CGAL_NO_UNIQUE_ADDRESS Store_kernel<AK_> sak;
+    CGAL_NO_UNIQUE_ADDRESS Store_kernel<EK_> sek;
     constexpr Cartesian_filter_K(){}
     constexpr Cartesian_filter_K(int d):Base_(d){}
     //FIXME: or do we want an instance of AK and EK belonging to this kernel,
     //instead of a reference to external ones?
-    constexpr Cartesian_filter_K(AK_ const&a,EK_ const&b):Base_(),Store_kernel<AK_>(a),Store_kernel2<EK_>(b){}
-    constexpr Cartesian_filter_K(int d,AK_ const&a,EK_ const&b):Base_(d),Store_kernel<AK_>(a),Store_kernel2<EK_>(b){}
+    constexpr Cartesian_filter_K(AK_ const&a,EK_ const&b):Base_(),sak(a),sek(b){}
+    constexpr Cartesian_filter_K(int d,AK_ const&a,EK_ const&b):Base_(d),sak(a),sek(b){}
     typedef Base_ Kernel_base;
     typedef AK_ AK;
     typedef EK_ EK;
     typedef typename Store_kernel<AK_>::reference_type AK_rt;
-    AK_rt approximate_kernel()const{return this->kernel();}
-    typedef typename Store_kernel2<EK_>::reference2_type EK_rt;
-    EK_rt exact_kernel()const{return this->kernel2();}
+    AK_rt approximate_kernel()const{return sak.kernel();}
+    typedef typename Store_kernel<EK_>::reference_type EK_rt;
+    EK_rt exact_kernel()const{return sek.kernel();}
 
     // MSVC is too dumb to perform the empty base optimization.
     typedef boost::mpl::and_<
@@ -52,12 +78,12 @@ struct Cartesian_filter_K : public Base_,
     // TODO: only fix some types, based on some criterion?
     template<class T> struct Type : Get_type<Kernel_base,T> {};
 
-    template<class T,class D=void,class=typename Get_functor_category<Cartesian_filter_K,T>::type> struct Functor :
+    template<class T,class D=void,class=typename Get_functor_category<Cartesian_filter_K,T>::type, bool=Pred_list::template contains<T>::value> struct Functor :
       Inherit_functor<Kernel_base,T,D> {};
-    template<class T,class D> struct Functor<T,D,Predicate_tag> {
+    template<class T,class D> struct Functor<T,D,Predicate_tag,true> {
       typedef typename Get_functor<AK, T>::type AP;
       typedef typename Get_functor<EK, T>::type EP;
-      typedef Filtered_predicate2<EP,AP,C2E,C2A> type;
+      typedef Filtered_predicate2<Cartesian_filter_K,EP,AP,C2E,C2A> type;
     };
 // TODO:
 //    template<class T> struct Functor<T,No_filter_tag,Predicate_tag> :
diff --git a/NewKernel_d/include/CGAL/NewKernel_d/Filtered_predicate2.h b/NewKernel_d/include/CGAL/NewKernel_d/Filtered_predicate2.h
index a6190e42b5a..c3d2281ad96 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/Filtered_predicate2.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/Filtered_predicate2.h
@@ -40,7 +40,7 @@ namespace CGAL {
 // - Some caching could be done at the Point_2 level.
 
 
-template <class EP, class AP, class C2E, class C2A, bool Protection = true>
+template <class K, class EP, class AP, class C2E, class C2A, bool Protection = true>
 class Filtered_predicate2
 {
 //TODO: pack (at least use a tuple)
@@ -65,7 +65,6 @@ public:
   Filtered_predicate2()
   {}
 
-  template <class K>
   Filtered_predicate2(const K& k)
     : ep(k.exact_kernel()), ap(k.approximate_kernel()), c2e(k,k.exact_kernel()), c2a(k,k.approximate_kernel())
   {}
diff --git a/NewKernel_d/include/CGAL/NewKernel_d/LA_eigen/LA.h b/NewKernel_d/include/CGAL/NewKernel_d/LA_eigen/LA.h
index 4dd8b5ca845..3d4afd905e5 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/LA_eigen/LA.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/LA_eigen/LA.h
@@ -21,6 +21,8 @@
 #include <Eigen/Dense>
 #include <CGAL/NewKernel_d/LA_eigen/constructors.h>
 #include <CGAL/iterator_from_indices.h>
+#include <CGAL/determinant.h>
+#include <CGAL/assertions.h>
 
 namespace CGAL {
 
@@ -100,15 +102,72 @@ template<class NT_,class Dim_,class Max_dim_=Dim_> struct LA_eigen {
                 return (int)v.cols();
         }
 
-        template<class Mat_> static NT determinant(Mat_ const&m,bool=false){
+        template<class Mat_> static NT determinant_aux [[noreturn]] (Mat_ const&, Tag_true) {
+                CGAL_error();
+        }
+        template<class Mat_> static NT determinant_aux(Mat_ const& m, Tag_false) {
                 return m.determinant();
         }
 
+        // TODO: https://gitlab.com/libeigen/eigen/-/issues/1782
+        // Implement a version of (sign_of_)determinant that works
+        // without (inexact) division in any dimension
+        template<class Mat_> static NT determinant(Mat_ const&m,bool=false){
+          switch(m.rows()){
+            //case 0:
+            //  return 1;
+            case 1:
+              return m(0,0);
+            case 2:
+              return CGAL::determinant(
+                  m(0,0),m(0,1),
+                  m(1,0),m(1,1));
+            case 3:
+              return CGAL::determinant(
+                  m(0,0),m(0,1),m(0,2),
+                  m(1,0),m(1,1),m(1,2),
+                  m(2,0),m(2,1),m(2,2));
+            case 4:
+              return CGAL::determinant(
+                  m(0,0),m(0,1),m(0,2),m(0,3),
+                  m(1,0),m(1,1),m(1,2),m(1,3),
+                  m(2,0),m(2,1),m(2,2),m(2,3),
+                  m(3,0),m(3,1),m(3,2),m(3,3));
+            case 5:
+              return CGAL::determinant(
+                  m(0,0),m(0,1),m(0,2),m(0,3),m(0,4),
+                  m(1,0),m(1,1),m(1,2),m(1,3),m(1,4),
+                  m(2,0),m(2,1),m(2,2),m(2,3),m(2,4),
+                  m(3,0),m(3,1),m(3,2),m(3,3),m(3,4),
+                  m(4,0),m(4,1),m(4,2),m(4,3),m(4,4));
+            case 6:
+              return CGAL::determinant(
+                  m(0,0),m(0,1),m(0,2),m(0,3),m(0,4),m(0,5),
+                  m(1,0),m(1,1),m(1,2),m(1,3),m(1,4),m(1,5),
+                  m(2,0),m(2,1),m(2,2),m(2,3),m(2,4),m(2,5),
+                  m(3,0),m(3,1),m(3,2),m(3,3),m(3,4),m(3,5),
+                  m(4,0),m(4,1),m(4,2),m(4,3),m(4,4),m(4,5),
+                  m(5,0),m(5,1),m(5,2),m(5,3),m(5,4),m(5,5));
+            case 7:
+              return CGAL::determinant(
+                  m(0,0),m(0,1),m(0,2),m(0,3),m(0,4),m(0,5),m(0,6),
+                  m(1,0),m(1,1),m(1,2),m(1,3),m(1,4),m(1,5),m(1,6),
+                  m(2,0),m(2,1),m(2,2),m(2,3),m(2,4),m(2,5),m(2,6),
+                  m(3,0),m(3,1),m(3,2),m(3,3),m(3,4),m(3,5),m(3,6),
+                  m(4,0),m(4,1),m(4,2),m(4,3),m(4,4),m(4,5),m(4,6),
+                  m(5,0),m(5,1),m(5,2),m(5,3),m(5,4),m(5,5),m(5,6),
+                  m(6,0),m(6,1),m(6,2),m(6,3),m(6,4),m(6,5),m(6,6));
+            default:
+              return determinant_aux(m, Boolean_tag<(Mat_::MaxRowsAtCompileTime >= 1 && Mat_::MaxRowsAtCompileTime <= 7)>());
+
+          }
+        }
+
         template<class Mat_> static typename
         Same_uncertainty_nt<CGAL::Sign, NT>::type
         sign_of_determinant(Mat_ const&m,bool=false)
         {
-                return CGAL::sign(m.determinant());
+                return CGAL::sign(LA_eigen::determinant(m));
         }
 
         template<class Mat_> static int rank(Mat_ const&m){
diff --git a/NewKernel_d/include/CGAL/NewKernel_d/Lazy_cartesian.h b/NewKernel_d/include/CGAL/NewKernel_d/Lazy_cartesian.h
index d9f4112cf68..56ecd5df953 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/Lazy_cartesian.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/Lazy_cartesian.h
@@ -56,10 +56,10 @@ namespace internal {
 // Whenever a construction takes iterator pairs as input, whether they point to double of Lazy objects, copy the ranges inside the lazy result so they are available for update_exact(). We analyze the input to try and guess where iterator pairs are. I would prefer if each functor had a specific signature (no overload in this layer) so we wouldn't have to guess.
 namespace Lazy_internal {
 template<class...>struct typelist{};
-template<int>struct arg_i{};
-template<int>struct arg_i_begin{};
-template<int>struct arg_i_end{};
-template<int>struct arg_i_ip1_range{};
+template<std::size_t>struct arg_i{};
+template<std::size_t>struct arg_i_begin{};
+template<std::size_t>struct arg_i_end{};
+template<std::size_t>struct arg_i_ip1_range{};
 template<class,class,class,class=void>struct analyze_args;
 template<class T,class U>struct analyze_args<T,U,typelist<>> {
   typedef T creator;
@@ -73,24 +73,24 @@ struct analyze_args<typelist<T...>,typelist<U...>,typelist<It,It,W...>,std::enab
 analyze_args<typelist<T...,arg_i_ip1_range<sizeof...(U)>>,typelist<U...,arg_i_begin<sizeof...(T)>,arg_i_end<sizeof...(T)>>,typelist<W...>> {};
 template<class...T> using analyze_args_for_lazy = analyze_args<typelist<>,typelist<>,typelist<T...>>;
 template<class,class>struct extract1;
-template<int i,class T>struct extract1<arg_i<i>,T>:std::tuple_element<i,T>{};
-template<int i,class T>struct extract1<arg_i_ip1_range<i>,T>{
+template<std::size_t i,class T>struct extract1<arg_i<i>,T>:std::tuple_element<i,T>{};
+template<std::size_t i,class T>struct extract1<arg_i_ip1_range<i>,T>{
   typedef std::tuple_element_t<i,T> E;
   typedef std::remove_cv_t<std::remove_reference_t<E>> It;
   typedef typename std::iterator_traits<It>::value_type element_type;
   // TODO: find a way to use an array of the right size, at least for the most frequent constructions
   typedef std::vector<element_type> type;
 };
-template<int i,class...T>decltype(auto)
+template<std::size_t i,class...T>decltype(auto)
 do_extract(arg_i<i>,std::tuple<T...>const&t)
 {return std::get<i>(t);}
-template<int i,class...T>decltype(auto)
+template<std::size_t i,class...T>decltype(auto)
 do_extract(arg_i_begin<i>,std::tuple<T...>const&t)
 {return std::begin(std::get<i>(t));}
-template<int i,class...T>decltype(auto)
+template<std::size_t i,class...T>decltype(auto)
 do_extract(arg_i_end<i>,std::tuple<T...>const&t)
 {return std::end(std::get<i>(t));}
-template<int i,class...T>decltype(auto)
+template<std::size_t i,class...T>decltype(auto)
 do_extract(arg_i_ip1_range<i>,std::tuple<T...>const&t)
 {
   typedef std::tuple<T...> L;
@@ -294,7 +294,7 @@ struct Lazy_cartesian :
     template<class T,class D> struct Functor<T,D,Predicate_tag> {
             typedef typename Get_functor<Approximate_kernel, T>::type FA;
             typedef typename Get_functor<Exact_kernel, T>::type FE;
-            typedef Filtered_predicate2<FE,FA,C2E,C2A> type;
+            typedef Filtered_predicate2<Lazy_cartesian,FE,FA,C2E,C2A> type;
     };
     template<class T,class D> struct Functor<T,D,Compute_tag> {
             typedef Lazy_construction2<T,Kernel> type;
diff --git a/NewKernel_d/include/CGAL/NewKernel_d/store_kernel.h b/NewKernel_d/include/CGAL/NewKernel_d/store_kernel.h
index b9bfe61749f..5249dff2fcb 100644
--- a/NewKernel_d/include/CGAL/NewKernel_d/store_kernel.h
+++ b/NewKernel_d/include/CGAL/NewKernel_d/store_kernel.h
@@ -13,12 +13,12 @@
 #define CGAL_STORE_KERNEL_H
 
 #include <CGAL/assertions.h>
-#include <boost/type_traits/is_empty.hpp>
+#include <type_traits>
 
 namespace CGAL {
 namespace internal {
 BOOST_MPL_HAS_XXX_TRAIT_DEF(Do_not_store_kernel)
-template<class T,bool=boost::is_empty<T>::value,bool=has_Do_not_store_kernel<T>::value> struct Do_not_store_kernel {
+template<class T,bool=std::is_empty<T>::value,bool=has_Do_not_store_kernel<T>::value> struct Do_not_store_kernel {
         enum { value=false };
         typedef Tag_false type;
 };
diff --git a/NewKernel_d/include/CGAL/argument_swaps.h b/NewKernel_d/include/CGAL/argument_swaps.h
index 85915098e26..a6f2cd8d794 100644
--- a/NewKernel_d/include/CGAL/argument_swaps.h
+++ b/NewKernel_d/include/CGAL/argument_swaps.h
@@ -18,9 +18,9 @@
 namespace CGAL {
 namespace internal {
 
-template<int,class...> struct Apply_to_last_then_rest_;
+template<std::size_t,class...> struct Apply_to_last_then_rest_;
 
-template<int d,class F,class T,class... U>
+template<std::size_t d,class F,class T,class... U>
 struct Apply_to_last_then_rest_<d,F,T,U...> {
         typedef typename Apply_to_last_then_rest_<d-1,F,U...,T>::result_type result_type;
         inline result_type operator()(F&&f,T&&t,U&&...u)const{
diff --git a/NewKernel_d/include/CGAL/typeset.h b/NewKernel_d/include/CGAL/typeset.h
index 9c494a412a9..77c37c89c39 100644
--- a/NewKernel_d/include/CGAL/typeset.h
+++ b/NewKernel_d/include/CGAL/typeset.h
@@ -41,11 +41,17 @@ namespace CGAL {
     template<class X> using contains = std::false_type;
     template<class X> using add = typeset<X>;
   };
+  struct typeset_all {
+    typedef typeset_all type;
+    template<class X> using contains = std::true_type;
+    template<class X> using add = typeset_all;
+  };
 
   template<class T1, class T2> struct typeset_union_ :
     typeset_union_<typename T1::template add<typename T2::head>::type, typename T2::tail>
   {};
   template<class T> struct typeset_union_ <T, typeset<> > : T {};
+  template<class T> struct typeset_union_ <T, typeset_all > : typeset_all {};
 
   template<class T1, class T2>
     struct typeset_intersection_ {
@@ -55,8 +61,8 @@ namespace CGAL {
         std::conditional<T2::template contains<H>::value,
         typename U::template add<H>::type, U>::type type;
     };
-  template<class T>
-    struct typeset_intersection_<typeset<>,T> : typeset<> {};
+  template<class T> struct typeset_intersection_<typeset<>, T> : typeset<> {};
+  template<class T> struct typeset_intersection_<typeset_all, T> : T {};
 
   template<class T1, class T2>
     using typeset_union = typename typeset_union_<T1,T2>::type;
diff --git a/NewKernel_d/test/NewKernel_d/CMakeLists.txt b/NewKernel_d/test/NewKernel_d/CMakeLists.txt
index e315981083a..ba586fee06d 100644
--- a/NewKernel_d/test/NewKernel_d/CMakeLists.txt
+++ b/NewKernel_d/test/NewKernel_d/CMakeLists.txt
@@ -17,9 +17,10 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "Epick_d.cpp" )
-    CGAL_target_use_Eigen(Epick_d)
+    target_link_libraries(Epick_d PUBLIC CGAL::Eigen_support)
   else()
 
     message(STATUS "NOTICE: This program requires the Eigen3 library, and will not be compiled.")
@@ -31,4 +32,3 @@ else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Number_types/include/CGAL/GMP/Gmpq_type.h b/Number_types/include/CGAL/GMP/Gmpq_type.h
index 54776eb5b78..451d2b00cdd 100644
--- a/Number_types/include/CGAL/GMP/Gmpq_type.h
+++ b/Number_types/include/CGAL/GMP/Gmpq_type.h
@@ -223,7 +223,7 @@ public:
   Gmpq& operator/=(const Gmpq &q);
 
   bool operator==(const Gmpq &q) const noexcept { return mpq_equal(this->mpq(), q.mpq()) != 0;}
-  bool operator< (const Gmpq &q) const noexcept { return mpq_cmp(this->mpq(), q.mpq()) < 0; }
+  bool operator< (const Gmpq &q) const { return mpq_cmp(this->mpq(), q.mpq()) < 0; }
 
   double to_double() const noexcept;
   Sign sign() const noexcept;
diff --git a/Number_types/include/CGAL/Lazy_exact_nt.h b/Number_types/include/CGAL/Lazy_exact_nt.h
index b0c401a3797..1a511325de9 100644
--- a/Number_types/include/CGAL/Lazy_exact_nt.h
+++ b/Number_types/include/CGAL/Lazy_exact_nt.h
@@ -438,6 +438,69 @@ public :
     return *this = new Lazy_exact_Div<ET>(*this, b);
   }
 
+  // Mixed comparisons with int.
+  friend bool operator<(const Lazy_exact_nt& a, int b)
+  {
+    CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
+    Uncertain<bool> res = a.approx() < b;
+    if (is_certain(res))
+      return res;
+    CGAL_BRANCH_PROFILER_BRANCH(tmp);
+    return a.exact() < b;
+  }
+
+  friend bool operator>(const Lazy_exact_nt& a, int b)
+  {
+    CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
+    Uncertain<bool> res = b < a.approx();
+    if (is_certain(res))
+      return get_certain(res);
+    CGAL_BRANCH_PROFILER_BRANCH(tmp);
+    return b < a.exact();
+  }
+
+  friend bool operator==(const Lazy_exact_nt& a, int b)
+  {
+    CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
+    Uncertain<bool> res = b == a.approx();
+    if (is_certain(res))
+      return get_certain(res);
+    CGAL_BRANCH_PROFILER_BRANCH(tmp);
+    return b == a.exact();
+  }
+
+
+  // Mixed comparisons with double.
+  friend bool operator<(const Lazy_exact_nt& a, double b)
+  {
+    CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
+    Uncertain<bool> res = a.approx() < b;
+    if (is_certain(res))
+      return res;
+    CGAL_BRANCH_PROFILER_BRANCH(tmp);
+    return a.exact() < b;
+  }
+
+  friend bool operator>(const Lazy_exact_nt& a, double b)
+  {
+    CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
+    Uncertain<bool> res = b < a.approx();
+    if (is_certain(res))
+      return res;
+    CGAL_BRANCH_PROFILER_BRANCH(tmp);
+    return b < a.exact();
+  }
+
+  friend bool operator==(const Lazy_exact_nt& a, double b)
+  {
+    CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
+    Uncertain<bool> res = b == a.approx();
+    if (is_certain(res))
+      return res;
+    CGAL_BRANCH_PROFILER_BRANCH(tmp);
+    return b == a.exact();
+  }
+
   // % kills filtering
   Self & operator%=(const Self& b)
   {
@@ -562,84 +625,6 @@ operator%(const Lazy_exact_nt<ET>& a, const Lazy_exact_nt<ET>& b)
 }
 
 
-
-// Mixed operators with int.
-template <typename ET>
-bool
-operator<(const Lazy_exact_nt<ET>& a, int b)
-{
-  CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
-  Uncertain<bool> res = a.approx() < b;
-  if (is_certain(res))
-    return res;
-  CGAL_BRANCH_PROFILER_BRANCH(tmp);
-  return a.exact() < b;
-}
-
-template <typename ET>
-bool
-operator>(const Lazy_exact_nt<ET>& a, int b)
-{
-  CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
-  Uncertain<bool> res = b < a.approx();
-  if (is_certain(res))
-    return get_certain(res);
-  CGAL_BRANCH_PROFILER_BRANCH(tmp);
-  return b < a.exact();
-}
-
-template <typename ET>
-bool
-operator==(const Lazy_exact_nt<ET>& a, int b)
-{
-  CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
-  Uncertain<bool> res = b == a.approx();
-  if (is_certain(res))
-    return get_certain(res);
-  CGAL_BRANCH_PROFILER_BRANCH(tmp);
-  return b == a.exact();
-}
-
-
-// Mixed operators with double.
-template <typename ET>
-bool
-operator<(const Lazy_exact_nt<ET>& a, double b)
-{
-  CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
-  Uncertain<bool> res = a.approx() < b;
-  if (is_certain(res))
-    return res;
-  CGAL_BRANCH_PROFILER_BRANCH(tmp);
-  return a.exact() < b;
-}
-
-template <typename ET>
-bool
-operator>(const Lazy_exact_nt<ET>& a, double b)
-{
-  CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
-  Uncertain<bool> res = b < a.approx();
-  if (is_certain(res))
-    return res;
-  CGAL_BRANCH_PROFILER_BRANCH(tmp);
-  return b < a.exact();
-}
-
-template <typename ET>
-bool
-operator==(const Lazy_exact_nt<ET>& a, double b)
-{
-  CGAL_BRANCH_PROFILER(std::string(" failures/calls to   : ") + std::string(CGAL_PRETTY_FUNCTION), tmp);
-  Uncertain<bool> res = b == a.approx();
-  if (is_certain(res))
-    return res;
-  CGAL_BRANCH_PROFILER_BRANCH(tmp);
-  return b == a.exact();
-}
-
-
-
 template <typename ET1, typename ET2>
 Lazy_exact_nt< typename Coercion_traits<ET1, ET2>::Type >
 operator+(const Lazy_exact_nt<ET1>& a, const Lazy_exact_nt<ET2>& b)
diff --git a/Number_types/include/CGAL/MP_Float.h b/Number_types/include/CGAL/MP_Float.h
index 56e22b7e39b..68cfdecde44 100644
--- a/Number_types/include/CGAL/MP_Float.h
+++ b/Number_types/include/CGAL/MP_Float.h
@@ -27,6 +27,7 @@
 #include <iostream>
 #include <vector>
 #include <algorithm>
+#include <boost/operators.hpp>
 
 // MP_Float : multiprecision scaled integers.
 
@@ -106,7 +107,13 @@ MP_Float operator*(const MP_Float &a, const MP_Float &b);
 MP_Float operator%(const MP_Float &a, const MP_Float &b);
 
 
-class MP_Float
+class MP_Float : boost::totally_ordered1<MP_Float
+#ifdef _MSC_VER
+                 , boost::ordered_ring_operators2<MP_Float, int
+                 , boost::ordered_ring_operators2<MP_Float, double
+                 > >
+#endif
+                 >
 {
 public:
   typedef short          limb;
@@ -223,6 +230,22 @@ public:
   MP_Float& operator*=(const MP_Float &a) { return *this = *this * a; }
   MP_Float& operator%=(const MP_Float &a) { return *this = *this % a; }
 
+  friend bool operator<(const MP_Float &a, const MP_Float &b)
+  { return INTERN_MP_FLOAT::compare(a, b) == SMALLER; }
+
+  friend bool operator==(const MP_Float &a, const MP_Float &b)
+  { return (a.v == b.v) && (a.v.empty() || (a.exp == b.exp)); }
+
+#ifdef _MSC_VER
+  // Needed because without /permissive-, it makes hidden friends visible (from Quotient)
+  friend bool operator==(const MP_Float &a, int    b) { return a == MP_Float(b); }
+  friend bool operator==(const MP_Float &a, double b) { return a == MP_Float(b); }
+  friend bool operator< (const MP_Float &a, int    b) { return a <  MP_Float(b); }
+  friend bool operator< (const MP_Float &a, double b) { return a <  MP_Float(b); }
+  friend bool operator> (const MP_Float &a, int    b) { return a >  MP_Float(b); }
+  friend bool operator> (const MP_Float &a, double b) { return a >  MP_Float(b); }
+#endif
+
   exponent_type max_exp() const
   {
     return exponent_type(v.size()) + exp;
@@ -365,30 +388,6 @@ inline
 void swap(MP_Float &m, MP_Float &n)
 { m.swap(n); }
 
-inline
-bool operator<(const MP_Float &a, const MP_Float &b)
-{ return INTERN_MP_FLOAT::compare(a, b) == SMALLER; }
-
-inline
-bool operator>(const MP_Float &a, const MP_Float &b)
-{ return b < a; }
-
-inline
-bool operator>=(const MP_Float &a, const MP_Float &b)
-{ return ! (a < b); }
-
-inline
-bool operator<=(const MP_Float &a, const MP_Float &b)
-{ return ! (a > b); }
-
-inline
-bool operator==(const MP_Float &a, const MP_Float &b)
-{ return (a.v == b.v) && (a.v.empty() || (a.exp == b.exp)); }
-
-inline
-bool operator!=(const MP_Float &a, const MP_Float &b)
-{ return ! (a == b); }
-
 MP_Float
 approximate_sqrt(const MP_Float &d);
 
diff --git a/Number_types/include/CGAL/Mpzf.h b/Number_types/include/CGAL/Mpzf.h
index d775431ebcf..2612e29b3a0 100644
--- a/Number_types/include/CGAL/Mpzf.h
+++ b/Number_types/include/CGAL/Mpzf.h
@@ -340,18 +340,62 @@ struct Mpzf {
     exp=x.exp;
     if(size!=0) mpn_copyi(data(),x.data(),asize);
   }
-#if !defined(CGAL_MPZF_USE_CACHE)
+#if defined(CGAL_MPZF_USE_CACHE)
+  Mpzf(Mpzf&& x)noexcept:size(x.size),exp(x.exp){
+    auto xd = x.data();
+    while(*--xd==0);
+    if (xd != x.cache) {
+      data() = x.data();
+      x.init();
+    } else {
+      init();
+      if(size!=0) mpn_copyi(data(),x.data(),std::abs(size));
+    }
+    x.size = 0;
+  }
+  Mpzf& operator=(Mpzf&& x)noexcept{
+    if (this == &x) return *this; // is this needed?
+    size = x.size;
+    exp = x.exp;
+    auto xd = x.data();
+    auto td = data();
+    while(*--xd==0);
+    while(*--td==0);
+    if (xd != x.cache) {
+      data() = x.data();
+      if (td != cache) {
+        pool::push(td+1);
+        // should we instead give it to x in case x is reused?
+        // x.data() = td + 1;
+      }
+      x.init();
+    } else {
+      // In some cases data points in the middle of the buffer, reset it
+      data() = td + 1;
+      if(size!=0) mpn_copyi(data(),x.data(),std::abs(size));
+    }
+    x.size = 0;
+    return *this;
+  }
+#else
   Mpzf(Mpzf&& x):data_(x.data()),size(x.size),exp(x.exp){
     x.init(); // yes, that's a shame...
     x.size = 0;
     x.exp = 0;
   }
-  Mpzf& operator=(Mpzf&& x){
-    std::swap(size,x.size);
+  Mpzf& operator=(Mpzf&& x)noexcept{
+    size = x.size;
+    // In case something tries to read it, size needs to be smaller than data
+    x.size = 0;
     exp = x.exp;
     std::swap(data(),x.data());
     return *this;
   }
+  friend void swap(Mpzf&a, Mpzf&b)noexcept{
+    std::swap(a.size, b.size);
+    std::swap(a.exp, b.exp);
+    std::swap(a.data(), b.data());
+  }
   friend Mpzf operator-(Mpzf&& x){
     Mpzf ret = std::move(x);
     ret.size = -ret.size;
@@ -534,6 +578,12 @@ struct Mpzf {
   friend bool operator!=(Mpzf const&a, Mpzf const&b){
     return !(a==b);
   }
+  friend Mpzf const& min BOOST_PREVENT_MACRO_SUBSTITUTION (Mpzf const&a, Mpzf const&b){
+    return (b<a)?b:a;
+  }
+  friend Mpzf const& max BOOST_PREVENT_MACRO_SUBSTITUTION (Mpzf const&a, Mpzf const&b){
+    return (a<b)?b:a;
+  }
   private:
   static Mpzf aors(Mpzf const&a, Mpzf const&b, int bsize){
     Mpzf res=noalloc();
@@ -846,6 +896,9 @@ struct Mpzf {
     }
   }
 
+  friend Mpzf operator+(Mpzf const&x){
+    return x;
+  }
   friend Mpzf operator-(Mpzf const&x){
     Mpzf ret = x;
     ret.size = -ret.size;
diff --git a/Number_types/include/CGAL/Quotient.h b/Number_types/include/CGAL/Quotient.h
index 38e5f834768..9e5ac07cb59 100644
--- a/Number_types/include/CGAL/Quotient.h
+++ b/Number_types/include/CGAL/Quotient.h
@@ -129,6 +129,15 @@ class Quotient
   Quotient<NT>& operator*= (const CGAL_double(NT)& r);
   Quotient<NT>& operator/= (const CGAL_double(NT)& r);
 
+  friend bool operator==(const Quotient& x, const Quotient& y)
+  { return x.num * y.den == x.den * y.num; }
+  friend bool operator==(const Quotient& x, const NT& y)
+  { return x.den * y == x.num; }
+  friend inline bool operator==(const Quotient& x, const CGAL_int(NT) & y)
+  { return x.den * y == x.num; }
+  friend inline bool operator==(const Quotient& x, const CGAL_double(NT) & y)
+  { return x.den * y == x.num; } // Uh?
+
   Quotient<NT>&    normalize();
 
   const NT&   numerator()   const { return num; }
@@ -438,31 +447,6 @@ quotient_truncation(const Quotient<NT>& r)
 
 
 
-template <class NT>
-CGAL_MEDIUM_INLINE
-bool
-operator==(const Quotient<NT>& x, const Quotient<NT>& y)
-{ return x.num * y.den == x.den * y.num; }
-
-template <class NT>
-CGAL_MEDIUM_INLINE
-bool
-operator==(const Quotient<NT>& x, const NT& y)
-{ return x.den * y == x.num; }
-
-template <class NT>
-inline
-bool
-operator==(const Quotient<NT>& x, const CGAL_int(NT) & y)
-{ return x.den * y == x.num; }
-
-template <class NT>
-inline
-bool
-operator==(const Quotient<NT>& x, const CGAL_double(NT) & y)
-{ return x.den * y == x.num; }
-
-
 
 template <class NT>
 CGAL_MEDIUM_INLINE
diff --git a/Number_types/test/Number_types/CMakeLists.txt b/Number_types/test/Number_types/CMakeLists.txt
index 37c64fa0b77..4f4cd1ab3b6 100644
--- a/Number_types/test/Number_types/CMakeLists.txt
+++ b/Number_types/test/Number_types/CMakeLists.txt
@@ -83,8 +83,9 @@ if ( CGAL_FOUND )
 
   create_single_source_cgal_program( "eigen.cpp" )
   find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
-  if (EIGEN3_FOUND)
-    cgal_target_use_Eigen(eigen)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
+    target_link_libraries(eigen PUBLIC CGAL::Eigen_support)
   endif()
 
 else( CGAL_FOUND )
diff --git a/Number_types/test/Number_types/Mpzf_new.cpp b/Number_types/test/Number_types/Mpzf_new.cpp
new file mode 100644
index 00000000000..414f1f2534b
--- /dev/null
+++ b/Number_types/test/Number_types/Mpzf_new.cpp
@@ -0,0 +1,40 @@
+#include <CGAL/config.h>
+
+#ifdef CGAL_USE_GMP
+# include <CGAL/Mpzf.h>
+#endif
+#ifdef CGAL_HAS_MPZF
+
+#include <iostream>
+#include <CGAL/Gmpq.h>
+#include <CGAL/Test/_test_algebraic_structure.h>
+#include <CGAL/Test/_test_real_embeddable.h>
+
+int main() {
+    {
+        typedef CGAL::Mpzf NT;
+        typedef CGAL::Integral_domain_without_division_tag Tag;
+        typedef CGAL::Tag_true Is_exact;
+
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>();
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(4),NT(6),NT(15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(-4),NT(6),NT(15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(4),NT(-6),NT(15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(-4),NT(-6),NT(15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(4),NT(6),NT(-15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(-4),NT(6), NT(15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(4),NT(-6),NT(-15));
+        CGAL::test_algebraic_structure<NT,Tag, Is_exact>(NT(-4),NT(-6),NT(-15));
+
+        CGAL::test_real_embeddable<NT>();
+    }
+
+    return 0;
+}
+
+#else
+int main()
+{
+  return 0;
+}
+#endif //CGAL_HAS_MPZF
diff --git a/Optimal_bounding_box/benchmarks/Optimal_bounding_box/CMakeLists.txt b/Optimal_bounding_box/benchmarks/Optimal_bounding_box/CMakeLists.txt
index 84cb0ab7dfc..86632a0be7c 100644
--- a/Optimal_bounding_box/benchmarks/Optimal_bounding_box/CMakeLists.txt
+++ b/Optimal_bounding_box/benchmarks/Optimal_bounding_box/CMakeLists.txt
@@ -16,10 +16,11 @@ endif()
 include( ${CGAL_USE_FILE} )
 
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
 
 create_single_source_cgal_program("bench_obb.cpp")
-CGAL_target_use_Eigen(bench_obb)
+target_link_libraries(bench_obb PUBLIC CGAL::Eigen_support)
diff --git a/Optimal_bounding_box/examples/Optimal_bounding_box/CMakeLists.txt b/Optimal_bounding_box/examples/Optimal_bounding_box/CMakeLists.txt
index 9a67221542e..9b657c24e1b 100644
--- a/Optimal_bounding_box/examples/Optimal_bounding_box/CMakeLists.txt
+++ b/Optimal_bounding_box/examples/Optimal_bounding_box/CMakeLists.txt
@@ -14,7 +14,8 @@ endif()
 include( ${CGAL_USE_FILE} )
 
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -27,5 +28,5 @@ foreach(target
         obb_example
         obb_with_point_maps_example
         rotated_aabb_tree_example)
-  CGAL_target_use_Eigen(${target})
+  target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
 endforeach()
diff --git a/Optimal_bounding_box/test/Optimal_bounding_box/CMakeLists.txt b/Optimal_bounding_box/test/Optimal_bounding_box/CMakeLists.txt
index c0ce4c74b4a..1ba260a6b92 100644
--- a/Optimal_bounding_box/test/Optimal_bounding_box/CMakeLists.txt
+++ b/Optimal_bounding_box/test/Optimal_bounding_box/CMakeLists.txt
@@ -14,7 +14,8 @@ endif()
 include( ${CGAL_USE_FILE} )
 
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -27,5 +28,5 @@ foreach(target
         test_OBB_traits
         test_nelder_mead
         test_optimization_algorithms)
-  CGAL_target_use_Eigen(${target})
+  target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
 endforeach()
diff --git a/Periodic_3_mesh_3/examples/Periodic_3_mesh_3/CMakeLists.txt b/Periodic_3_mesh_3/examples/Periodic_3_mesh_3/CMakeLists.txt
index bcb9a3247c0..0b936e2c370 100644
--- a/Periodic_3_mesh_3/examples/Periodic_3_mesh_3/CMakeLists.txt
+++ b/Periodic_3_mesh_3/examples/Periodic_3_mesh_3/CMakeLists.txt
@@ -23,7 +23,8 @@ endif()
 
 # Use Eigen
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -52,5 +53,5 @@ foreach(target
     mesh_implicit_shape_with_subdomains
     mesh_implicit_shape_with_optimizers
     mesh_implicit_shape_with_features)
-  CGAL_target_use_Eigen(${target})
+  target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
 endforeach()
diff --git a/Periodic_3_mesh_3/test/Periodic_3_mesh_3/CMakeLists.txt b/Periodic_3_mesh_3/test/Periodic_3_mesh_3/CMakeLists.txt
index 3a3f69e79d7..ceba5546a54 100644
--- a/Periodic_3_mesh_3/test/Periodic_3_mesh_3/CMakeLists.txt
+++ b/Periodic_3_mesh_3/test/Periodic_3_mesh_3/CMakeLists.txt
@@ -16,21 +16,21 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-  if (NOT EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (NOT TARGET CGAL::Eigen_support)
     message(STATUS "This project requires the Eigen library, and will not be compiled.")
     return()
   endif()
 
   create_single_source_cgal_program( "test_implicit_shapes_bunch.cpp" )
-  CGAL_target_use_Eigen(test_implicit_shapes_bunch)
+  target_link_libraries(test_implicit_shapes_bunch PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program( "test_implicit_shapes_with_features.cpp" )
-  CGAL_target_use_Eigen(test_implicit_shapes_with_features)
+  target_link_libraries(test_implicit_shapes_with_features PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program( "test_triply_periodic_minimal_surfaces.cpp" )
-  CGAL_target_use_Eigen(test_triply_periodic_minimal_surfaces)
+  target_link_libraries(test_triply_periodic_minimal_surfaces PUBLIC CGAL::Eigen_support)
 
 else()
 
   message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_cell_base_3.h b/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_cell_base_3.h
index 1109c4a0181..7b475e9a11e 100644
--- a/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_cell_base_3.h
+++ b/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_cell_base_3.h
@@ -233,7 +233,7 @@ public:
 
   // For use by Compact_container.
   void * for_compact_container() const { return N[0].for_compact_container(); }
-  void * & for_compact_container()     { return N[0].for_compact_container(); }
+  void for_compact_container(void *p) { N[0].for_compact_container(p); }
 
   // TDS internal data access functions.
   TDS_data& tds_data() { return _tds_data; }
diff --git a/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_vertex_base_3.h b/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_vertex_base_3.h
index 539c3278bf3..e264e523063 100644
--- a/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_vertex_base_3.h
+++ b/Periodic_3_triangulation_3/include/CGAL/Periodic_3_triangulation_ds_vertex_base_3.h
@@ -80,8 +80,8 @@ public:
   // For use by the Compact_container.
   void *   for_compact_container() const
   { return _c.for_compact_container(); }
-  void * & for_compact_container()
-  { return _c.for_compact_container(); }
+  void for_compact_container(void *p)
+  { _c.for_compact_container(p); }
 
 private:
   Cell_handle _c;
diff --git a/Point_set_3/examples/Point_set_3/CMakeLists.txt b/Point_set_3/examples/Point_set_3/CMakeLists.txt
index 172e045e4d2..cc8a77fb8b6 100644
--- a/Point_set_3/examples/Point_set_3/CMakeLists.txt
+++ b/Point_set_3/examples/Point_set_3/CMakeLists.txt
@@ -44,9 +44,10 @@ set(needed_cxx_features cxx_rvalue_references cxx_variadic_templates)
 create_single_source_cgal_program( "point_set_read_ply.cpp" CXX_FEATURES ${needed_cxx_features} )
 
 find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
+include(CGAL_Eigen_support)
 if (EIGEN3_FOUND)
   create_single_source_cgal_program( "point_set_algo.cpp" )
-  CGAL_target_use_Eigen(point_set_algo)
+  target_link_libraries(point_set_algo PUBLIC CGAL::Eigen_support)
 endif()
 
 create_single_source_cgal_program("draw_point_set_3.cpp" )
diff --git a/Point_set_processing_3/doc/Point_set_processing_3/Point_set_processing_3.txt b/Point_set_processing_3/doc/Point_set_processing_3/Point_set_processing_3.txt
index 1d8a90ca53c..1ee0474f796 100644
--- a/Point_set_processing_3/doc/Point_set_processing_3/Point_set_processing_3.txt
+++ b/Point_set_processing_3/doc/Point_set_processing_3/Point_set_processing_3.txt
@@ -645,11 +645,12 @@ computed and stored as colors in a PLY file:
 
 \section Point_set_processing_3OutlierRemoval Outlier Removal
 
-Function `remove_outliers()` deletes a user-specified fraction
-of outliers from an input point set. More specifically, it sorts the
-input points in increasing order of average squared distances to their
-nearest neighbors and deletes the points with largest value. The user
-can either specify a fixed number of nearest neighbors or a fixed
+Function `remove_outliers()` deletes a user-specified fraction of
+outliers from an input point set. More specifically, it partitions the
+input points with respect to the average squared distances to their
+nearest neighbors and deletes the points with largest value, either
+partitionning with a threshold or removing a fixed percentage. The
+user can either specify a fixed number of nearest neighbors or a fixed
 spherical neighborhood radius.
 
 \subsection Point_set_processing_3Example_outlier_removal Example
diff --git a/Point_set_processing_3/examples/Point_set_processing_3/CMakeLists.txt b/Point_set_processing_3/examples/Point_set_processing_3/CMakeLists.txt
index 85f5f79eed8..83253368016 100644
--- a/Point_set_processing_3/examples/Point_set_processing_3/CMakeLists.txt
+++ b/Point_set_processing_3/examples/Point_set_processing_3/CMakeLists.txt
@@ -31,117 +31,101 @@ if ( CGAL_FOUND )
          "Enable concurrency"
          OFF)
 
+  set(CGAL_libs CGAL::CGAL)
   if( CGAL_ACTIVATE_CONCURRENT_PSP3 OR ENV{CGAL_ACTIVATE_CONCURRENT_PSP3} )
     find_package( TBB REQUIRED )
+    include(CGAL_TBB_support)
+    if (TARGET CGAL::TBB_support)
+      set(CGAL_TBB_target ${CGAL_libs} CGAL::TBB_support)
+    endif()
   endif()
 
   # Executables that do *not* require EIGEN
-  create_single_source_cgal_program( "average_spacing_example.cpp" )
-  create_single_source_cgal_program( "bilateral_smooth_point_set_example.cpp" )
-  create_single_source_cgal_program( "grid_simplification_example.cpp" )
-  create_single_source_cgal_program( "grid_simplify_indices.cpp" )
-  create_single_source_cgal_program( "property_map.cpp" )
-  create_single_source_cgal_program( "random_simplification_example.cpp" )
-  create_single_source_cgal_program( "read_write_xyz_point_set_example.cpp" )
-  create_single_source_cgal_program( "remove_outliers_example.cpp" )
-  create_single_source_cgal_program( "wlop_simplify_and_regularize_point_set_example.cpp" )
-  create_single_source_cgal_program( "edge_aware_upsample_point_set_example.cpp" )
-  create_single_source_cgal_program( "structuring_example.cpp" )
-
-  create_single_source_cgal_program( "read_ply_points_with_colors_example.cpp" )
-  create_single_source_cgal_program( "write_ply_points_example.cpp" )
+  foreach(target
+      average_spacing_example
+      bilateral_smooth_point_set_example
+      grid_simplification_example
+      grid_simplify_indices
+      property_map
+      random_simplification_example
+      read_write_xyz_point_set_example
+      remove_outliers_example
+      wlop_simplify_and_regularize_point_set_example
+      edge_aware_upsample_point_set_example
+      structuring_example
+      read_ply_points_with_colors_example
+      write_ply_points_example)
+    add_executable(${target} "${target}.cpp")
+    target_link_libraries(${target} ${CGAL_libs})
+  endforeach()
 
   find_package(LASLIB)
-  if (LASLIB_FOUND)
-    create_single_source_cgal_program( "read_las_example.cpp" )
-    CGAL_target_use_LASLIB(read_las_example)
+  include(CGAL_LASLIB_support)
+  if (TARGET CGAL::LASLIB_support)
+    add_executable( read_las_example "read_las_example.cpp" )
+    target_link_libraries(read_las_example ${CGAL_libs} CGAL::LASLIB_support)
   else()
     message(STATUS "NOTICE : the LAS reader test requires LASlib and will not be compiled.")
   endif()
 
   # Use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
+    set(CGAL_libs ${CGAL_libs} CGAL::Eigen_support)
+
     # Executables that require Eigen
-    create_single_source_cgal_program( "jet_smoothing_example.cpp" )
-    CGAL_target_use_Eigen(jet_smoothing_example)
-
-    create_single_source_cgal_program( "normal_estimation.cpp" )
-    CGAL_target_use_Eigen(normal_estimation)
-
-    create_single_source_cgal_program( "clustering_example.cpp" )
-    CGAL_target_use_Eigen(clustering_example)
-
-    create_single_source_cgal_program( "edges_example.cpp" )
-    CGAL_target_use_Eigen(edges_example)
+    foreach(target
+        jet_smoothing_example
+        normal_estimation
+        clustering_example
+        edges_example
+        callback_example
+        scale_estimation_example
+        scale_estimation_2d_example
+        hierarchy_simplification_example
+        normals_example)
+      add_executable(${target} "${target}.cpp")
+      target_link_libraries(${target} ${CGAL_libs})
+    endforeach()
 
     # Executables that require libpointmatcher
     find_package(libpointmatcher QUIET)
-    if (libpointmatcher_FOUND)
-      create_single_source_cgal_program( "registration_with_pointmatcher.cpp" )
-      CGAL_target_use_pointmatcher(registration_with_pointmatcher)
-      CGAL_target_use_Eigen(registration_with_pointmatcher)
+    include(CGAL_pointmatcher_support)
+    if (TARGET CGAL::pointmatcher_support)
+      add_executable(registration_with_pointmatcher "registration_with_pointmatcher.cpp")
+      target_link_libraries(registration_with_pointmatcher
+        ${CGAL_libs} CGAL::pointmatcher_support)
     else()
       message(STATUS "NOTICE : the registration_with_pointmatcher test requires libpointmatcher and will not be compiled.")
     endif()
 
     # Executables that require OpenGR
     find_package(OpenGR QUIET)
-    if (OpenGR_FOUND)
-      create_single_source_cgal_program( "registration_with_OpenGR.cpp" )
-      CGAL_target_use_OpenGR(registration_with_OpenGR)
-      CGAL_target_use_Eigen(registration_with_OpenGR)
+    include(CGAL_OpenGR_support)
+    if (TARGET CGAL::OpenGR_support)
+      add_executable(registration_with_OpenGR "registration_with_OpenGR.cpp" )
+      target_link_libraries(registration_with_OpenGR
+        ${CGAL_libs} CGAL::OpenGR_support)
     else()
       message(STATUS "NOTICE : registration_with_OpenGR requires OpenGR, and will not be compiled.")
     endif()
 
     # Executables that require both libpointmatcher and OpenGR
-    if (libpointmatcher_FOUND AND OpenGR_FOUND)
-      create_single_source_cgal_program( "registration_with_opengr_pointmatcher_pipeline.cpp" )
-      CGAL_target_use_OpenGR(registration_with_opengr_pointmatcher_pipeline)
-      CGAL_target_use_pointmatcher(registration_with_opengr_pointmatcher_pipeline)
-      CGAL_target_use_Eigen(registration_with_opengr_pointmatcher_pipeline)
+    if (TARGET CGAL::pointmatcher_support AND
+        TARGET CGAL::OpenGR_support)
+      add_executable(registration_with_opengr_pointmatcher_pipeline
+        "registration_with_opengr_pointmatcher_pipeline.cpp" )
+      target_link_libraries(registration_with_opengr_pointmatcher_pipeline
+        ${CGAL_libs} CGAL::pointmatcher_support CGAL::OpenGR_support)
     else()
       message(STATUS "NOTICE : registration_with_opengr_pointmatcher_pipeline requires libpointmatcher and OpenGR, and will not be compiled.")
     endif()
 
-    create_single_source_cgal_program( "callback_example.cpp" )
-    CGAL_target_use_Eigen(callback_example)
-
-    create_single_source_cgal_program( "scale_estimation_example.cpp" )
-    CGAL_target_use_Eigen(scale_estimation_example)
-
-    create_single_source_cgal_program( "scale_estimation_2d_example.cpp" )
-    CGAL_target_use_Eigen(scale_estimation_2d_example)
-
-    create_single_source_cgal_program( "hierarchy_simplification_example.cpp" )
-    CGAL_target_use_Eigen(hierarchy_simplification_example)
-
-    create_single_source_cgal_program( "normals_example.cpp" )
-    CGAL_target_use_Eigen(normals_example)
-
   else()
     message(STATUS "NOTICE: Some of the executables in this directory need Eigen 3.1 (or greater) and will not be compiled.")
   endif()
 
-  if (TBB_FOUND)
-    foreach(target
-        scale_estimation_example
-        wlop_simplify_and_regularize_point_set_example
-        bilateral_smooth_point_set_example
-        edge_aware_upsample_point_set_example
-        average_spacing_example
-        normals_example
-        jet_smoothing_example
-        normal_estimation
-        callback_example
-        clustering_example)
-      if(TARGET ${target})
-        CGAL_target_use_TBB(${target})
-      endif()
-    endforeach()
-  endif()
-
 else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 endif()
diff --git a/Point_set_processing_3/examples/Point_set_processing_3/remove_outliers_example.cpp b/Point_set_processing_3/examples/Point_set_processing_3/remove_outliers_example.cpp
index caadef5aa25..0c390fb6e7c 100644
--- a/Point_set_processing_3/examples/Point_set_processing_3/remove_outliers_example.cpp
+++ b/Point_set_processing_3/examples/Point_set_processing_3/remove_outliers_example.cpp
@@ -37,7 +37,7 @@ int main(int argc, char*argv[])
   // FIRST OPTION //
   // I don't know the ratio of outliers present in the point set
   std::vector<Point>::iterator first_to_remove
-    = CGAL::remove_outliers
+    = CGAL::remove_outliers<CGAL::Parallel_if_available_tag>
     (points,
      nb_neighbors,
      CGAL::parameters::threshold_percent (100.). // No limit on the number of outliers to remove
@@ -53,7 +53,7 @@ int main(int argc, char*argv[])
   // I know the ratio of outliers present in the point set
   const double removed_percentage = 5.0; // percentage of points to remove
 
-  points.erase(CGAL::remove_outliers
+  points.erase(CGAL::remove_outliers<CGAL::Parallel_if_available_tag>
                (points,
                 nb_neighbors,
                 CGAL::parameters::threshold_percent(removed_percentage). // Minimum percentage to remove
diff --git a/Point_set_processing_3/include/CGAL/remove_outliers.h b/Point_set_processing_3/include/CGAL/remove_outliers.h
index 611269da396..ce5b7154879 100644
--- a/Point_set_processing_3/include/CGAL/remove_outliers.h
+++ b/Point_set_processing_3/include/CGAL/remove_outliers.h
@@ -17,6 +17,8 @@
 #include <CGAL/disable_warnings.h>
 
 #include <CGAL/Point_set_processing_3/internal/Neighbor_query.h>
+#include <CGAL/Point_set_processing_3/internal/Callback_wrapper.h>
+#include <CGAL/for_each.h>
 #include <CGAL/property_map.h>
 #include <CGAL/point_set_processing_assertions.h>
 #include <functional>
@@ -24,6 +26,8 @@
 #include <CGAL/boost/graph/Named_function_parameters.h>
 #include <CGAL/boost/graph/named_params_helper.h>
 
+#include <boost/iterator/zip_iterator.hpp>
+
 #include <iterator>
 #include <algorithm>
 #include <map>
@@ -84,7 +88,9 @@ compute_avg_knn_sq_distance_3(
    \ingroup PkgPointSetProcessing3Algorithms
    Removes outliers:
    - computes average squared distance to the nearest neighbors,
-   - and sorts the points in increasing order of average distance.
+   - and partitions the points either using a threshold on the of
+     average distance or selecting a fixed percentage of points with
+     the highest average distances
 
    This method modifies the order of input points so as to pack all remaining points first,
    and returns an iterator over the first point to remove (see erase-remove idiom).
@@ -92,6 +98,8 @@ compute_avg_knn_sq_distance_3(
 
    \pre `k >= 2`
 
+   \tparam ConcurrencyTag enables sequential versus parallel algorithm. Possible values are `Sequential_tag`,
+                          `Parallel_tag`, and `Parallel_if_available_tag`.
    \tparam PointRange is a model of `Range`. The value type of
    its iterator is the key type of the named parameter `point_map`.
 
@@ -132,7 +140,8 @@ compute_avg_knn_sq_distance_3(
    account; if `threshold_distance=0` only `threshold_percent` is
    taken into account.
 */
-template <typename PointRange,
+template <typename ConcurrencyTag,
+          typename PointRange,
           typename NamedParameters
 >
 typename PointRange::iterator
@@ -162,9 +171,6 @@ remove_outliers(
   typedef typename PointRange::iterator iterator;
   typedef typename iterator::value_type value_type;
 
-  // actual type of input points
-  typedef typename std::iterator_traits<typename PointRange::iterator>::value_type Enriched_point;
-
   // types for K nearest neighbors search structure
   typedef Point_set_processing_3::internal::Neighbor_query<Kernel, PointRange&, PointMap> Neighbor_query;
 
@@ -183,48 +189,76 @@ remove_outliers(
   std::size_t nb_points = points.size();
 
   // iterate over input points and add them to multimap sorted by distance to k
-  std::multimap<FT,Enriched_point> sorted_points;
-  std::size_t nb = 0;
-  for(const value_type& vt : points)
+  std::vector<std::pair<FT, value_type> > sorted_points;
+  sorted_points.reserve (nb_points);
+  for (const value_type& p : points)
+    sorted_points.push_back(std::make_pair (FT(0), p));
+
+  Point_set_processing_3::internal::Callback_wrapper<ConcurrencyTag>
+    callback_wrapper (callback, nb_points);
+
+  CGAL::for_each<ConcurrencyTag>
+    (sorted_points,
+     [&](std::pair<FT, value_type>& p) -> bool
+     {
+       if (callback_wrapper.interrupted())
+         return false;
+
+       p.first = internal::compute_avg_knn_sq_distance_3(
+         get(point_map, p.second),
+         neighbor_query, k, neighbor_radius);
+
+       ++ callback_wrapper.advancement();
+       return true;
+     });
+
+  std::size_t first_index_to_remove = std::size_t(double(sorted_points.size()) * ((100.0-threshold_percent)/100.0));
+
+  typename std::vector<std::pair<FT, value_type> >::iterator f2r
+    = sorted_points.begin();
+
+  if (threshold_distance != FT(0))
+    f2r = std::partition (sorted_points.begin(), sorted_points.end(),
+                          [&threshold_distance](const std::pair<FT, value_type>& p) -> bool
+                          {
+                            return p.first < threshold_distance * threshold_distance;
+                          });
+
+  if (static_cast<std::size_t>(std::distance (sorted_points.begin(), f2r)) < first_index_to_remove)
   {
-    FT sq_distance = internal::compute_avg_knn_sq_distance_3(
-      get(point_map, vt),
-      neighbor_query, k, neighbor_radius);
-    sorted_points.insert( std::make_pair(sq_distance, vt) );
-    if (callback && !callback ((nb+1) / double(nb_points)))
-      return points.end();
-    ++ nb;
+    std::nth_element (f2r,
+                      sorted_points.begin() + first_index_to_remove,
+                      sorted_points.end());
+    f2r = sorted_points.begin() + first_index_to_remove;
   }
 
-  // Replaces [points.begin(), points.end()) range by the multimap content.
-  // Returns the iterator after the (100-threshold_percent) % best points.
-  typename PointRange::iterator first_point_to_remove = points.begin();
-  typename PointRange::iterator dst = points.begin();
-  int first_index_to_remove = int(double(sorted_points.size()) * ((100.0-threshold_percent)/100.0));
-  typename std::multimap<FT,Enriched_point>::iterator src;
-  int index;
-  for (src = sorted_points.begin(), index = 0;
-       src != sorted_points.end();
-       ++src, ++index)
+  // Replaces [points.begin(), points.end()) range by the sorted content.
+  iterator pit = points.begin();
+  iterator out = points.begin();
+
+  for (auto sit = sorted_points.begin(); sit != sorted_points.end(); ++ sit)
   {
-    *dst++ = src->second;
-    if (index <= first_index_to_remove ||
-        src->first < threshold_distance * threshold_distance)
-      first_point_to_remove = dst;
+    *pit = sit->second;
+    if (sit == f2r)
+      out = pit;
+    ++ pit;
   }
 
-  return first_point_to_remove;
+  callback_wrapper.join();
+
+  // Returns the iterator on the first point to remove
+  return out;
 }
 
 /// \cond SKIP_IN_MANUAL
 // variant with default NP
-template <typename PointRange>
+template <typename ConcurrencyTag, typename PointRange>
 typename PointRange::iterator
 remove_outliers(
   PointRange& points,
   unsigned int k) ///< number of neighbors.
 {
-  return remove_outliers (points, k, CGAL::Point_set_processing_3::parameters::all_default(points));
+  return remove_outliers<ConcurrencyTag> (points, k, CGAL::Point_set_processing_3::parameters::all_default(points));
 }
 /// \endcond
 
diff --git a/Point_set_processing_3/test/Point_set_processing_3/CMakeLists.txt b/Point_set_processing_3/test/Point_set_processing_3/CMakeLists.txt
index cf3ef3053c4..f35e24e2f50 100644
--- a/Point_set_processing_3/test/Point_set_processing_3/CMakeLists.txt
+++ b/Point_set_processing_3/test/Point_set_processing_3/CMakeLists.txt
@@ -27,6 +27,7 @@ if ( CGAL_FOUND )
   ADD_DEFINITIONS( "-DDEBUG_TRACE" )
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
 
   # Executables that do *not* require Eigen
   create_single_source_cgal_program( "read_test.cpp" )
@@ -49,30 +50,31 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
+  include(CGAL_Eigen_support)
   if (EIGEN3_FOUND)
     # Executables that require Eigen
     create_single_source_cgal_program( "normal_estimation_test.cpp" )
-    CGAL_target_use_Eigen(normal_estimation_test)
+    target_link_libraries(normal_estimation_test PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "hierarchy_simplification_test.cpp" )
-    CGAL_target_use_Eigen(hierarchy_simplification_test)
+    target_link_libraries(hierarchy_simplification_test PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "smoothing_test.cpp" )
-    CGAL_target_use_Eigen(smoothing_test)
+    target_link_libraries(smoothing_test PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "vcm_plane_test.cpp" )
-    CGAL_target_use_Eigen(vcm_plane_test)
+    target_link_libraries(vcm_plane_test PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "vcm_all_test.cpp" )
-    CGAL_target_use_Eigen(vcm_all_test)
+    target_link_libraries(vcm_all_test PUBLIC CGAL::Eigen_support)
 
     create_single_source_cgal_program( "jet_pointer_as_property_map.cpp" )
-    CGAL_target_use_Eigen(jet_pointer_as_property_map)
+    target_link_libraries(jet_pointer_as_property_map PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "NOTICE: This program requires Eigen 3.1 (or greater) and will not be compiled.")
   endif()
 
-  if (TBB_FOUND)
+  if (TARGET CGAL::TBB_support)
     foreach(target
         analysis_test
         smoothing_test
@@ -81,7 +83,7 @@ if ( CGAL_FOUND )
         edge_aware_upsample_test
         normal_estimation_test)
       if(TARGET ${target})
-        CGAL_target_use_TBB(${target})
+        target_link_libraries(${target} PUBLIC CGAL::TBB_support)
       endif()
     endforeach()
   endif()
@@ -91,4 +93,3 @@ else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Point_set_processing_3/test/Point_set_processing_3/remove_outliers_test.cpp b/Point_set_processing_3/test/Point_set_processing_3/remove_outliers_test.cpp
index fc12a99ec1a..50e552d928b 100644
--- a/Point_set_processing_3/test/Point_set_processing_3/remove_outliers_test.cpp
+++ b/Point_set_processing_3/test/Point_set_processing_3/remove_outliers_test.cpp
@@ -50,8 +50,9 @@ void test_avg_knn_sq_distance(std::deque<Point>& points, // input point set
             << nb_neighbors_remove_outliers << ")...\n";
 
   // Removes outliers using erase-remove idiom
-  points.erase(CGAL::remove_outliers(points, nb_neighbors_remove_outliers,
-                                     CGAL::parameters::threshold_percent(removed_percentage)),
+  points.erase(CGAL::remove_outliers<CGAL::Parallel_if_available_tag>
+               (points, nb_neighbors_remove_outliers,
+                CGAL::parameters::threshold_percent(removed_percentage)),
                points.end());
 
   // Optional: after erase(), use Scott Meyer's "swap trick" to trim excess capacity
@@ -139,4 +140,3 @@ int main(int argc, char * argv[])
   std::cerr << "Tool returned " << accumulated_fatal_err << std::endl;
   return accumulated_fatal_err;
 }
-
diff --git a/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/CMakeLists.txt b/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/CMakeLists.txt
index a7eb729ec77..b67981f06b6 100644
--- a/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/CMakeLists.txt
+++ b/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/CMakeLists.txt
@@ -23,16 +23,17 @@ if ( CGAL_FOUND )
 
   # Find Eigen3 (requires 3.1.0 or greater)
   find_package(Eigen3 3.1.0)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     # Executables that require Eigen 3
     create_single_source_cgal_program( "poisson_reconstruction_example.cpp" )
-    CGAL_target_use_Eigen(poisson_reconstruction_example)
+    target_link_libraries(poisson_reconstruction_example PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "poisson_reconstruction.cpp" )
-    CGAL_target_use_Eigen(poisson_reconstruction)
+    target_link_libraries(poisson_reconstruction PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "poisson_reconstruction_function.cpp" )
-    CGAL_target_use_Eigen(poisson_reconstruction_function)
+    target_link_libraries(poisson_reconstruction_function PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "tutorial_example.cpp" )
-    CGAL_target_use_Eigen(tutorial_example)
+    target_link_libraries(tutorial_example PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "NOTICE: The examples need Eigen 3.1 (or greater) will not be compiled.")
   endif()
@@ -43,4 +44,3 @@ else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/tutorial_example.cpp b/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/tutorial_example.cpp
index ff58e34ed31..594961714d4 100644
--- a/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/tutorial_example.cpp
+++ b/Poisson_surface_reconstruction_3/examples/Poisson_surface_reconstruction_3/tutorial_example.cpp
@@ -63,9 +63,10 @@ int main(int argc, char*argv[])
   ///////////////////////////////////////////////////////////////////
   //! [Outlier removal]
 
-  CGAL::remove_outliers (points,
-                         24, // Number of neighbors considered for evaluation
-                         points.parameters().threshold_percent (5.0)); // Percentage of points to remove
+  CGAL::remove_outliers<CGAL::Sequential_tag>
+    (points,
+     24, // Number of neighbors considered for evaluation
+     points.parameters().threshold_percent (5.0)); // Percentage of points to remove
 
   std::cout << points.number_of_removed_points()
             << " point(s) are outliers." << std::endl;
diff --git a/Poisson_surface_reconstruction_3/test/Poisson_surface_reconstruction_3/CMakeLists.txt b/Poisson_surface_reconstruction_3/test/Poisson_surface_reconstruction_3/CMakeLists.txt
index 1c518a1267b..b8cb454be73 100644
--- a/Poisson_surface_reconstruction_3/test/Poisson_surface_reconstruction_3/CMakeLists.txt
+++ b/Poisson_surface_reconstruction_3/test/Poisson_surface_reconstruction_3/CMakeLists.txt
@@ -24,10 +24,11 @@ if ( CGAL_FOUND )
   # Temporary debugging stuff
 
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if(EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if(TARGET CGAL::Eigen_support)
     # Executables that require Eigen 3.1
     create_single_source_cgal_program( "poisson_reconstruction_test.cpp" )
-    CGAL_target_use_Eigen(poisson_reconstruction_test)
+    target_link_libraries(poisson_reconstruction_test PUBLIC CGAL::Eigen_support)
   else()
 
     message(STATUS "NOTICE: Some of the executables in this directory need Eigen 3.1 (or greater) and will not be compiled.")
@@ -39,4 +40,3 @@ else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Polygon_mesh_processing/benchmark/Polygon_mesh_processing/CMakeLists.txt b/Polygon_mesh_processing/benchmark/Polygon_mesh_processing/CMakeLists.txt
index 33c8b074104..008b892cd43 100644
--- a/Polygon_mesh_processing/benchmark/Polygon_mesh_processing/CMakeLists.txt
+++ b/Polygon_mesh_processing/benchmark/Polygon_mesh_processing/CMakeLists.txt
@@ -29,6 +29,7 @@ endif()
 
 # include for local package
 find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
 # Creating entries for all .cpp/.C files with "main" routine
 # ##########################################################
@@ -37,8 +38,7 @@ create_single_source_cgal_program( "polygon_mesh_slicer.cpp" )
 
 create_single_source_cgal_program( "hole_filling.cpp" )
 
-if (EIGEN3_FOUND)
-  CGAL_target_use_Eigen(polygon_mesh_slicer)
-  CGAL_target_use_Eigen(hole_filling)
+if (TARGET CGAL::Eigen_support)
+  target_link_libraries(polygon_mesh_slicer PUBLIC CGAL::Eigen_support)
+  target_link_libraries(hole_filling PUBLIC CGAL::Eigen_support)
 endif()
-
diff --git a/Polygon_mesh_processing/examples/Polygon_mesh_processing/CMakeLists.txt b/Polygon_mesh_processing/examples/Polygon_mesh_processing/CMakeLists.txt
index 151f4fe333c..46a7f04d886 100644
--- a/Polygon_mesh_processing/examples/Polygon_mesh_processing/CMakeLists.txt
+++ b/Polygon_mesh_processing/examples/Polygon_mesh_processing/CMakeLists.txt
@@ -38,6 +38,7 @@ endif()
 
 # include for local package
 find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
 
 # Creating entries for all .cpp/.C files with "main" routine
@@ -45,18 +46,18 @@ find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
 
 create_single_source_cgal_program( "hausdorff_distance_remeshing_example.cpp")
 
-if (EIGEN3_FOUND)
+if (TARGET CGAL::Eigen_support)
   create_single_source_cgal_program( "hole_filling_example.cpp" )
-  CGAL_target_use_Eigen(hole_filling_example)
+  target_link_libraries(hole_filling_example PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program( "hole_filling_example_SM.cpp" )
-  CGAL_target_use_Eigen(hole_filling_example_SM)
+  target_link_libraries(hole_filling_example_SM PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program( "refine_fair_example.cpp")
-  CGAL_target_use_Eigen(refine_fair_example)
+  target_link_libraries(refine_fair_example PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program( "shape_smoothing_example.cpp")
-  CGAL_target_use_Eigen(shape_smoothing_example)
+  target_link_libraries(shape_smoothing_example PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program( "hole_filling_example_LCC.cpp" )
-  CGAL_target_use_Eigen(hole_filling_example_LCC)
-endif(EIGEN3_FOUND)
+  target_link_libraries(hole_filling_example_LCC PUBLIC CGAL::Eigen_support)
+endif()
 
 create_single_source_cgal_program( "self_intersections_example.cpp" )
 create_single_source_cgal_program( "stitch_borders_example.cpp" )
@@ -98,10 +99,9 @@ if(OpenMesh_FOUND)
 create_single_source_cgal_program( "compute_normals_example_OM.cpp" )
 target_link_libraries( compute_normals_example_OM PRIVATE ${OPENMESH_LIBRARIES} )
 
-if (EIGEN3_FOUND)
+if (TARGET CGAL::Eigen_support)
   create_single_source_cgal_program( "hole_filling_example_OM.cpp" )
-  target_link_libraries( hole_filling_example_OM PRIVATE ${OPENMESH_LIBRARIES} )
-  CGAL_target_use_Eigen( hole_filling_example_OM )
+  target_link_libraries( hole_filling_example_OM PRIVATE CGAL::Eigen_support ${OPENMESH_LIBRARIES} )
 endif()
 
 create_single_source_cgal_program( "point_inside_example_OM.cpp")
@@ -118,9 +118,10 @@ target_link_libraries( triangulate_faces_example_OM PRIVATE ${OPENMESH_LIBRARIES
 endif(OpenMesh_FOUND)
 
 find_package( TBB )
-if( TBB_FOUND )
-  CGAL_target_use_TBB(self_intersections_example)
-  CGAL_target_use_TBB(hausdorff_distance_remeshing_example)
+include(CGAL_TBB_support)
+if( TARGET CGAL::TBB_support )
+  target_link_libraries(self_intersections_example PUBLIC CGAL::TBB_support)
+  target_link_libraries(hausdorff_distance_remeshing_example PUBLIC CGAL::TBB_support)
 else()
   message( STATUS "NOTICE: Intel TBB was not found. Sequential code will be used." )
 endif()
diff --git a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/distance.h b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/distance.h
index 0f8aeb511a0..08f6d8c997d 100644
--- a/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/distance.h
+++ b/Polygon_mesh_processing/include/CGAL/Polygon_mesh_processing/distance.h
@@ -29,7 +29,7 @@
 #include <CGAL/spatial_sort.h>
 
 #ifdef CGAL_LINKED_WITH_TBB
-#include <tbb/parallel_for.h>
+#include <tbb/parallel_reduce.h>
 #include <tbb/blocked_range.h>
 #include <atomic>
 #endif // CGAL_LINKED_WITH_TBB
@@ -81,21 +81,27 @@ struct Distance_computation{
   const AABB_tree& tree;
   const PointRange& sample_points;
   Point_3 initial_hint;
-  std::atomic<double>* distance;
-
+  double distance;
+  //constructor
   Distance_computation(
           const AABB_tree& tree,
           const Point_3& p,
-          const PointRange& sample_points,
-          std::atomic<double>* d)
+          const PointRange& sample_points)
     : tree(tree)
     , sample_points(sample_points)
     , initial_hint(p)
-    , distance(d)
+    , distance(-1)
+  {}
+  //split constructor
+  Distance_computation(Distance_computation& s, tbb::split )
+    : tree(s.tree)
+    , sample_points(s.sample_points)
+    , initial_hint(s.initial_hint)
+    , distance(-1)
   {}
 
   void
-  operator()(const tbb::blocked_range<std::size_t>& range) const
+  operator()(const tbb::blocked_range<std::size_t>& range)
   {
     Point_3 hint = initial_hint;
     double hdist = 0;
@@ -107,15 +113,11 @@ struct Distance_computation{
       if(d > hdist)
         hdist=d;
     }
-
-    // update max value stored in distance
-    double current_value = *distance;
-    while( current_value < hdist )
-    {
-      if(distance->compare_exchange_weak(current_value, hdist))
-        current_value = hdist;
-    }
+    if(hdist > distance)
+      distance = hdist;
   }
+
+  void join( Distance_computation& rhs ) {distance = (std::max)(rhs.distance, distance); }
 };
 #endif
 
@@ -136,9 +138,9 @@ double approximate_Hausdorff_distance_impl(
   {
     std::atomic<double> distance;
     distance=0;
-    Distance_computation<AABBTree, PointRange> f(tree, hint, sample_points, &distance);
-    tbb::parallel_for(tbb::blocked_range<std::size_t>(0, sample_points.size()), f);
-    return distance;
+    Distance_computation<AABBTree, PointRange> f(tree, hint, sample_points);
+    tbb::parallel_reduce(tbb::blocked_range<std::size_t>(0, sample_points.size()), f);
+    return f.distance;
   }
   else
 #endif
diff --git a/Polygon_mesh_processing/test/Polygon_mesh_processing/CMakeLists.txt b/Polygon_mesh_processing/test/Polygon_mesh_processing/CMakeLists.txt
index 84ed2997d2b..6c0c88bd4b7 100644
--- a/Polygon_mesh_processing/test/Polygon_mesh_processing/CMakeLists.txt
+++ b/Polygon_mesh_processing/test/Polygon_mesh_processing/CMakeLists.txt
@@ -31,22 +31,24 @@ endif()
 
 # include for local package
 find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
 find_package( TBB )
+include(CGAL_TBB_support)
 
-if (EIGEN3_FOUND)
+if (TARGET CGAL::Eigen_support)
   # Creating entries for all .cpp/.C files with "main" routine
   # ##########################################################
   create_single_source_cgal_program("fairing_test.cpp")
-  CGAL_target_use_Eigen(fairing_test)
+  target_link_libraries(fairing_test PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program("triangulate_hole_Polyhedron_3_no_delaunay_test.cpp" )
-  CGAL_target_use_Eigen(triangulate_hole_Polyhedron_3_no_delaunay_test)
+  target_link_libraries(triangulate_hole_Polyhedron_3_no_delaunay_test PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program("triangulate_hole_Polyhedron_3_test.cpp")
-  CGAL_target_use_Eigen(triangulate_hole_Polyhedron_3_test)
+  target_link_libraries(triangulate_hole_Polyhedron_3_test PUBLIC CGAL::Eigen_support)
   create_single_source_cgal_program("test_shape_smoothing.cpp")
-  CGAL_target_use_Eigen(test_shape_smoothing)
+  target_link_libraries(test_shape_smoothing PUBLIC CGAL::Eigen_support)
 
-endif(EIGEN3_FOUND)
+endif()
 
 find_package( OpenMesh QUIET )
 if ( OpenMesh_FOUND )
@@ -104,11 +106,10 @@ endif()
   create_single_source_cgal_program("test_pmp_read_polygon_mesh.cpp")
 #  create_single_source_cgal_program("test_pmp_repair_self_intersections.cpp")
 
-  if( TBB_FOUND )
-    include(CGAL_target_use_TBB)
-    CGAL_target_use_TBB(test_pmp_distance)
-    CGAL_target_use_TBB(orient_polygon_soup_test)
-    CGAL_target_use_TBB(self_intersection_surface_mesh_test)
+  if( TARGET CGAL::TBB_support )
+    target_link_libraries(test_pmp_distance PUBLIC CGAL::TBB_support)
+    target_link_libraries(orient_polygon_soup_test PUBLIC CGAL::TBB_support)
+    target_link_libraries(self_intersection_surface_mesh_test PUBLIC CGAL::TBB_support)
   else()
     message( STATUS "NOTICE: Intel TBB was not found. test_pmp_distance will use sequential code." )
   endif()
diff --git a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt
index 5fd39e6bcc1..68eec9daba7 100644
--- a/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt
+++ b/Polygonal_surface_reconstruction/examples/Polygonal_surface_reconstruction/CMakeLists.txt
@@ -37,15 +37,18 @@ endif()
 include( CGAL_CreateSingleSourceCGALProgram )
 
 find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-if(NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if(NOT TARGET CGAL::Eigen_support)
   message(STATUS "NOTICE: This project requires Eigen 3.1 (or greater) and will not be compiled.")
   return()
 endif()
 
 find_package(SCIP QUIET)
-if (NOT SCIP_FOUND )
+include(CGAL_SCIP_support)
+if (NOT TARGET CGAL::SCIP_support )
   find_package( GLPK QUIET)
-  if ( NOT GLPK_FOUND )
+  include(CGAL_GLPK_support)
+  if (NOT TARGET CGAL::GLPK_support )
     message( STATUS "NOTICE: This project requires either SCIP or GLPK, and will not be compiled.")
     return()
   endif()
@@ -61,10 +64,10 @@ foreach(target
     polyfit_example_user_provided_planes
     polyfit_example_model_complexty_control
     polyfit_example_with_region_growing)
-  CGAL_target_use_Eigen(${target})
-  if (SCIP_FOUND)
-    CGAL_target_use_SCIP(${target})
+  target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
+  if (TARGET CGAL::SCIP_support)
+    target_link_libraries(${target} PUBLIC CGAL::SCIP_support)
   else()
-    CGAL_target_use_GLPK(${target})
+    target_link_libraries(${target} PUBLIC CGAL::GLPK_support)
   endif()
 endforeach()
diff --git a/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt b/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt
index fb12c54a420..7ce3ba34320 100644
--- a/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt
+++ b/Polygonal_surface_reconstruction/test/Polygonal_surface_reconstruction/CMakeLists.txt
@@ -38,24 +38,27 @@ include( CGAL_CreateSingleSourceCGALProgram )
 
 
 find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-if(NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if(NOT TARGET CGAL::Eigen_support)
   message(STATUS "NOTICE: This project requires Eigen 3.1 (or greater) and will not be compiled.")
   return()
 endif()
 
 find_package(SCIP QUIET)
-if (NOT SCIP_FOUND )
+include(CGAL_SCIP_support)
+if (NOT TARGET CGAL::SCIP_support )
   find_package( GLPK QUIET)
-  if ( NOT GLPK_FOUND )
-    message( STATUS "NOTICE : This project requires either SCIP or GLPK, and will not be compiled.")
+  include(CGAL_GLPK_support)
+  if (NOT TARGET CGAL::GLPK_support )
+    message( STATUS "NOTICE: This project requires either SCIP or GLPK, and will not be compiled.")
     return()
   endif()
 endif()
 
 create_single_source_cgal_program( "polygonal_surface_reconstruction_test.cpp")
-CGAL_target_use_Eigen(polygonal_surface_reconstruction_test)
-if (SCIP_FOUND)
-  CGAL_target_use_SCIP(polygonal_surface_reconstruction_test)
+target_link_libraries(polygonal_surface_reconstruction_test PUBLIC CGAL::Eigen_support)
+if (TARGET CGAL::SCIP_support)
+  target_link_libraries(polygonal_surface_reconstruction_test PUBLIC CGAL::SCIP_support)
 else()
-  CGAL_target_use_GLPK(polygonal_surface_reconstruction_test)
+  target_link_libraries(polygonal_surface_reconstruction_test PUBLIC CGAL::GLPK_support)
 endif()
diff --git a/Polyhedron/demo/Polyhedron/CMakeLists.txt b/Polyhedron/demo/Polyhedron/CMakeLists.txt
index 9e00808a516..55cf03849d1 100644
--- a/Polyhedron/demo/Polyhedron/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/CMakeLists.txt
@@ -73,6 +73,7 @@ if(Qt5_FOUND)
 endif(Qt5_FOUND)
 
 find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
 find_package( METIS )
 
@@ -87,7 +88,8 @@ option(POLYHEDRON_DEMO_ACTIVATE_CONCURRENCY
 
 if( POLYHEDRON_DEMO_ACTIVATE_CONCURRENCY )
   find_package( TBB )
-  if( NOT TBB_FOUND )
+  include(CGAL_TBB_support)
+  if( NOT TARGET CGAL::TBB_support )
     message( STATUS "NOTICE: Intel TBB was not found. Bilateral smoothing and WLOP plugins are faster if TBB is linked." )
   endif()
 endif()
@@ -108,7 +110,8 @@ if( CGAL_ACTIVATE_CONCURRENT_MESH_3 OR ENV{CGAL_ACTIVATE_CONCURRENT_MESH_3} )
   add_definitions( -DCGAL_CONCURRENT_MESH_3 )
   if(NOT TBB_FOUND)
     find_package( TBB REQUIRED )
-    if( NOT TBB_FOUND )
+    include( CGAL_TBB_support)
+    if( NOT TARGET CGAL::TBB_support )
       message(STATUS "NOTICE: Intel TBB was not found. Mesh_3 is faster if TBB is linked.")
     endif()
   endif()
@@ -119,6 +122,7 @@ else( CGAL_ACTIVATE_CONCURRENT_MESH_3 OR ENV{CGAL_ACTIVATE_CONCURRENT_MESH_3} )
     ON)
   if( LINK_WITH_TBB )
     find_package( TBB )
+    include( CGAL_TBB_support)
   endif( LINK_WITH_TBB )
 endif()
 
@@ -248,8 +252,8 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND)
 
   add_item(scene_c3t3_item Scene_c3t3_item.cpp)
   target_link_libraries(scene_c3t3_item PUBLIC scene_surface_mesh_item scene_polygon_soup_item scene_basic_objects ${TBB_LIBRARIES})
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(scene_c3t3_item)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(scene_c3t3_item PUBLIC CGAL::TBB_support)
   endif()
   if(COMMAND target_precompile_headers)
     # Support for precompiled headers, for Mesh_3 (since CMake 3.16)
@@ -261,7 +265,7 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND)
   add_item(scene_surface_mesh_item Scene_surface_mesh_item.cpp)
 
   if(TBB_FOUND)
-    CGAL_target_use_TBB(scene_surface_mesh_item)
+    target_link_libraries(scene_surface_mesh_item PUBLIC CGAL::TBB_support)
   endif()
   # special
 
@@ -274,7 +278,7 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND)
   add_item(scene_selection_item Scene_polyhedron_selection_item.cpp)
   target_link_libraries(scene_selection_item PUBLIC scene_item_decorator  scene_k_ring_selection)
  if(TBB_FOUND)
-    CGAL_target_use_TBB(scene_selection_item)
+    target_link_libraries(scene_selection_item PUBLIC CGAL::TBB_support)
   endif()
 
   add_item(scene_shortest_path_item Plugins/Surface_mesh/Scene_polyhedron_shortest_path_item.cpp)
@@ -282,17 +286,16 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND)
 
   add_item(scene_movable_sm_item Plugins/AABB_tree/Scene_movable_sm_item.cpp)
 
-  if(EIGEN3_FOUND )
+  if(TARGET CGAL::Eigen_support )
     add_item(scene_textured_item Scene_textured_surface_mesh_item.cpp texture.cpp)
-    CGAL_target_use_Eigen(scene_textured_item)
+    target_link_libraries(scene_textured_item PUBLIC CGAL::Eigen_support)
     qt5_wrap_ui( editionUI_FILES Plugins/Surface_mesh_deformation/Deform_mesh.ui )
     add_item(scene_edit_item Plugins/Surface_mesh_deformation/Scene_edit_polyhedron_item.cpp
       ${editionUI_FILES})
-    CGAL_target_use_Eigen(scene_edit_item)
-    target_link_libraries(scene_edit_item PUBLIC scene_surface_mesh_item scene_k_ring_selection
+    target_link_libraries(scene_edit_item PUBLIC CGAL::Eigen_support scene_surface_mesh_item scene_k_ring_selection
       scene_basic_objects)
     add_item(scene_mcf_item Plugins/PMP/Scene_mcf_item.cpp)
-    CGAL_target_use_Eigen(scene_mcf_item)
+    target_link_libraries(scene_mcf_item PUBLIC CGAL::Eigen_support)
   endif()
 
   add_item(scene_implicit_function_item Scene_implicit_function_item.cpp )
@@ -305,20 +308,21 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND)
   target_link_libraries(scene_nef_polyhedron_item PUBLIC scene_surface_mesh_item)
 
   add_item(scene_points_with_normal_item Scene_points_with_normal_item.cpp)
-  if (EIGEN3_FOUND)
-    CGAL_target_use_Eigen(scene_points_with_normal_item)
+  if (TARGET CGAL::Eigen_support)
+    target_link_libraries(scene_points_with_normal_item PUBLIC CGAL::Eigen_support)
   endif()
 
   find_package(LASLIB)
-  if (LASLIB_FOUND)
-    CGAL_target_use_LASLIB(scene_points_with_normal_item)
+  include(CGAL_LASLIB_support)
+  if (TARGET CGAL::LASLIB_support)
+    target_link_libraries(scene_points_with_normal_item PUBLIC CGAL::LASLIB_support)
     if (MSVC)
       target_compile_definitions( scene_points_with_normal_item PUBLIC "-D_CRT_SECURE_NO_DEPRECATE -D_CRT_SECURE_NO_WARNINGS")
     endif()
   endif()
 
   if(TBB_FOUND)
-    CGAL_target_use_TBB(scene_points_with_normal_item)
+    target_link_libraries(scene_points_with_normal_item PUBLIC CGAL::TBB_support)
   endif()
 
   add_item(scene_polylines_item Scene_polylines_item.cpp)
@@ -402,6 +406,13 @@ add_executable  ( CGAL_PMP PMP.cpp )
 add_dependencies(CGAL_PMP PMP)
 target_link_libraries( CGAL_PMP PRIVATE polyhedron_demo )
 add_to_cached_list( CGAL_EXECUTABLE_TARGETS CGAL_PMP )
+
+#WS Server
+if(TARGET Qt5::WebSockets)
+  add_executable  (WS_server Server_ws.cpp)
+  target_link_libraries(WS_server PUBLIC Qt5::WebSockets)
+  message(STATUS "Qt5WebSockets was found. Using WebSockets is therefore possible.")
+endif()
 #
 # Exporting
 #
diff --git a/Polyhedron/demo/Polyhedron/MainWindow.cpp b/Polyhedron/demo/Polyhedron/MainWindow.cpp
index bd370cd7827..3951ba10c1c 100644
--- a/Polyhedron/demo/Polyhedron/MainWindow.cpp
+++ b/Polyhedron/demo/Polyhedron/MainWindow.cpp
@@ -77,12 +77,6 @@
 #include "Color_map.h"
 
 
-#ifdef CGAL_USE_WEBSOCKETS
-#include <QWebSocketServer>
-#include <QWebSocket>
-#include <QNetworkInterface>
-#endif
-
 using namespace CGAL::Three;
 QScriptValue
 myScene_itemToScriptValue(QScriptEngine *engine,
@@ -1033,7 +1027,7 @@ void MainWindow::computeViewerBBox(CGAL::qglviewer::Vec& vmin, CGAL::qglviewer::
   double l_dist = (std::max)((std::abs)(bbox_center.x - viewer->offset().x),
                              (std::max)((std::abs)(bbox_center.y - viewer->offset().y),
                                         (std::abs)(bbox_center.z - viewer->offset().z)));
-  if((std::log2)(l_dist/bbox_diag) > 13.0 )
+  if((std::log2)(l_dist/bbox_diag) > 11.0 )
     for(int i=0; i<3; ++i)
     {
       offset[i] = -bbox_center[i];
@@ -2940,25 +2934,12 @@ void MainWindow::on_actionSa_ve_Scene_as_Script_triggered()
   bool do_upload = false;
 #ifdef CGAL_USE_SSH
   QString user = settings.value("ssh_user", QString()).toString();
-  QString pass;
   if(!user.isEmpty())
   {
     QMessageBox::StandardButton doyou =
         QMessageBox::question(this, tr("Upload ?"), tr("Do you wish to upload the scene"
                                                        " using the SSH preferences ?"));
-    bool ok;
     do_upload = (doyou == QMessageBox::Yes);
-    if(do_upload)
-    {
-      pass = QInputDialog::getText(this, "SSH Password",
-                                   "Enter ssh key password:",
-                                   QLineEdit::Password,
-                                   tr(""),
-                                   &ok);
-      if(!ok)
-        return;
-      pass = pass.trimmed();
-    }
   }
 #endif
 
@@ -3109,12 +3090,31 @@ void MainWindow::on_actionSa_ve_Scene_as_Script_triggered()
       path.prepend("Polyhedron_demo_");
     try{
       ssh_session session;
-      bool res = establish_ssh_session(session,
-                            user.toStdString().c_str(),
-                            server.toStdString().c_str(),
-                            pk.toStdString().c_str(),
-                            privK.toStdString().c_str(),
-                            pass.toStdString().c_str());
+      bool res = establish_ssh_session_from_agent(session,
+                                                  user.toStdString().c_str(),
+                                                  server.toStdString().c_str(),
+                                                  pk.toStdString().c_str());
+
+      if(!res)
+      {
+        bool ok;
+        QString pass;
+        pass = QInputDialog::getText(this, "SSH Password",
+                                     "Enter ssh key password:",
+                                     QLineEdit::Password,
+                                     tr(""),
+                                     &ok);
+        if(!ok)
+          return;
+        pass = pass.trimmed();
+        res = establish_ssh_session(session,
+                                    user.toStdString().c_str(),
+                                    server.toStdString().c_str(),
+                                    pk.toStdString().c_str(),
+                                    privK.toStdString().c_str(),
+                                    pass.toStdString().c_str());
+      }
+
       if(!res)
       {
         QMessageBox::warning(this,
@@ -3590,25 +3590,13 @@ void MainWindow::on_actionLoad_a_Scene_from_a_Script_File_triggered()
 
 #ifdef CGAL_USE_SSH
   QString user = settings.value("ssh_user", QString()).toString();
-  QString pass;
+
   if(!user.isEmpty())
   {
     QMessageBox::StandardButton doyou =
         QMessageBox::question(this, tr("Download ?"), tr("Do you wish to download the scene"
                                                          " using the SSH preferences ?"));
-    bool ok;
     do_download= (doyou == QMessageBox::Yes);
-    if(do_download)
-    {
-      pass = QInputDialog::getText(this, "SSH Password",
-                                   "Enter ssh key password:",
-                                   QLineEdit::Password,
-                                   tr(""),
-                                   &ok);
-      if(!ok)
-        return;
-      pass = pass.trimmed();
-    }
   }
 #endif
 
@@ -3623,22 +3611,30 @@ void MainWindow::on_actionLoad_a_Scene_from_a_Script_File_triggered()
     server = server.trimmed();
     pk = pk.trimmed();
     privK=privK.trimmed();
-    QString path;
-    path = QInputDialog::getText(this,
-                                 "",
-                                 tr("Enter the name of the scene file."));
-    if(path.isEmpty())
-      return;
-    if(!path.contains("Polyhedron_demo_"))
-      path.prepend("Polyhedron_demo_");
+
     try{
       ssh_session session;
-      bool res = establish_ssh_session(session,
-                            user.toStdString().c_str(),
-                            server.toStdString().c_str(),
-                            pk.toStdString().c_str(),
-                            privK.toStdString().c_str(),
-                            pass.toStdString().c_str());
+      bool res = establish_ssh_session_from_agent(session,
+                                                  user.toStdString().c_str(),
+                                                  server.toStdString().c_str(),
+                                                  pk.toStdString().c_str());
+      if(!res){
+        bool ok;
+        QString pass= QInputDialog::getText(this, "SSH Password",
+                                     "Enter ssh key password:",
+                                     QLineEdit::Password,
+                                     tr(""),
+                                     &ok);
+        if(!ok)
+          return;
+        pass = pass.trimmed();
+        res = establish_ssh_session(session,
+                                    user.toStdString().c_str(),
+                                    server.toStdString().c_str(),
+                                    pk.toStdString().c_str(),
+                                    privK.toStdString().c_str(),
+                                    pass.toStdString().c_str());
+      }
       if(!res)
       {
         QMessageBox::warning(this,
@@ -3646,7 +3642,22 @@ void MainWindow::on_actionLoad_a_Scene_from_a_Script_File_triggered()
                              "The SSH session could not be started.");
         return;
       }
+      QStringList names;
+      if(!CGAL::ssh_internal::explore_the_galaxy(session, names))
+      {
+        QMessageBox::warning(this,
+                             "Error",
+                             "Could not find remote directory.");
+      }
+      QString path;
+      path = QInputDialog::getItem(this,
+                                   "Choose a file",
+                                   tr("Choose the scene file."),
+                                   names);
       filename = QString("%1/load_scene.js").arg(QDir::tempPath());
+      if(path.isEmpty())
+        return;
+      path.prepend("Polyhedron_demo_");
       path = tr("/tmp/%2").arg(path);
       res = pull_file(session,path.toStdString().c_str(), filename.toStdString().c_str());
       if(!res)
@@ -3681,90 +3692,3 @@ void MainWindow::on_actionLoad_a_Scene_from_a_Script_File_triggered()
     tmp_file.remove();
   }
 }
-
-#ifdef CGAL_USE_WEBSOCKETS
-void MainWindow::on_action_Start_a_Session_triggered()
-{
-  QAction * action= findChild<QAction*>("action_Start_a_Session");
-  static EchoServer *server =nullptr;
-  if(action->isChecked()){
-     server = new EchoServer(1234);
-    QObject::connect(server, &EchoServer::closed, server,&EchoServer::deleteLater);
-  }
-  else
-  {
-    server->deleteLater();
-  }
-}
-
-EchoServer::EchoServer(quint16 port) :
-    QObject(CGAL::Three::Three::mainWindow()),
-    m_pWebSocketServer(new QWebSocketServer(QStringLiteral("Echo Server"),
-                                            QWebSocketServer::NonSecureMode, this))
-{
-    if (m_pWebSocketServer->listen(QHostAddress::Any, port)) {
-        connect(m_pWebSocketServer, &QWebSocketServer::newConnection,
-                this, &EchoServer::onNewConnection);
-        connect(m_pWebSocketServer, &QWebSocketServer::closed, this, &EchoServer::closed);
-    }
-    QHostAddress local_host("0.0.0.0");
-
-    //to avoid printing 127.0.0.1. Not realy sure it won't ever print the external ipv4 though.
-    const QHostAddress &localhost = QHostAddress(QHostAddress::LocalHost);
-    for (const QHostAddress &address: QNetworkInterface::allAddresses()) {
-      if (address.protocol() == QAbstractSocket::IPv4Protocol && address != localhost)
-      {
-        local_host= address;
-        break;
-      }
-    }
-    QMessageBox mb(QMessageBox::NoIcon, "WS Server",
-                   tr("WebSockets Server started.\nEnter the following address in\nyour Network Preferences to be able to join it :\n"
-                      "ws://%1:%2").arg(local_host.toString()).arg(port), QMessageBox::Ok, CGAL::Three::Three::mainWindow());
-    mb.setTextInteractionFlags(Qt::TextSelectableByMouse);
-    mb.exec();
-}
-
-EchoServer::~EchoServer()
-{
-    m_pWebSocketServer->close();
-    qDeleteAll(m_clients.begin(), m_clients.end());
-}
-
-void EchoServer::onNewConnection()
-{
-    QWebSocket *pSocket = m_pWebSocketServer->nextPendingConnection();
-
-    connect(pSocket, &QWebSocket::textMessageReceived, this, &EchoServer::processTextMessage);
-    connect(pSocket, &QWebSocket::binaryMessageReceived, this, &EchoServer::processBinaryMessage);
-    connect(pSocket, &QWebSocket::disconnected, this, &EchoServer::socketDisconnected);
-
-    m_clients << pSocket;
-}
-
-void EchoServer::processTextMessage(QString message)
-{
-    QWebSocket *pClient = qobject_cast<QWebSocket *>(sender());
-    for(auto *client : m_clients) {
-      if(client != pClient)
-        client->sendTextMessage(message);
-    }
-}
-
-void EchoServer::processBinaryMessage(QByteArray message)
-{
-    QWebSocket *pClient = qobject_cast<QWebSocket *>(sender());
-    if (pClient) {
-        pClient->sendBinaryMessage(message);
-    }
-}
-
-void EchoServer::socketDisconnected()
-{
-    QWebSocket *pClient = qobject_cast<QWebSocket *>(sender());
-    if (pClient) {
-        m_clients.removeAll(pClient);
-        pClient->deleteLater();
-    }
-}
-#endif
diff --git a/Polyhedron/demo/Polyhedron/MainWindow.h b/Polyhedron/demo/Polyhedron/MainWindow.h
index 4e544c08378..8f681a3b3c8 100644
--- a/Polyhedron/demo/Polyhedron/MainWindow.h
+++ b/Polyhedron/demo/Polyhedron/MainWindow.h
@@ -354,10 +354,6 @@ protected Q_SLOTS:
   void save(QString filename, QList<CGAL::Three::Scene_item*>& to_save);
   //!Calls the function saveSnapShot of the viewer.
   void on_actionSaveSnapshot_triggered();
-#ifdef CGAL_USE_WEBSOCKETS
-  //!Starts a new WS server if none is already exist. Else, does nothing.
-  void on_action_Start_a_Session_triggered();
-#endif
   //!Opens a Dialog to choose a color and make it the background color.
   void setBackgroundColor();
   //!Opens a Dialog to change the lighting settings
@@ -501,30 +497,5 @@ protected:
 private:
   bool is_main;
 };
-#ifdef CGAL_USE_WEBSOCKETS
-QT_FORWARD_DECLARE_CLASS(QWebSocketServer)
-QT_FORWARD_DECLARE_CLASS(QWebSocket)
 
-class EchoServer : public QObject
-{
-    Q_OBJECT
-public:
-    explicit EchoServer(quint16 port);
-    ~EchoServer();
-
-
-Q_SIGNALS:
-    void closed();
-
-private Q_SLOTS:
-    void onNewConnection();
-    void processTextMessage(QString message);
-    void processBinaryMessage(QByteArray message);
-    void socketDisconnected();
-
-private:
-    QWebSocketServer *m_pWebSocketServer;
-    QList<QWebSocket *> m_clients;
-};
-#endif
 #endif // ifndef MAINWINDOW_H
diff --git a/Polyhedron/demo/Polyhedron/MainWindow.ui b/Polyhedron/demo/Polyhedron/MainWindow.ui
index 6273a37bd16..a56c2c1afe8 100644
--- a/Polyhedron/demo/Polyhedron/MainWindow.ui
+++ b/Polyhedron/demo/Polyhedron/MainWindow.ui
@@ -97,7 +97,6 @@
     <addaction name="action_Rearrange_Viewers"/>
     <addaction name="menuDockWindows"/>
     <addaction name="separator"/>
-    <addaction name="action_Start_a_Session"/>
    </widget>
    <addaction name="menuFile"/>
    <addaction name="menuEdit"/>
@@ -470,17 +469,6 @@
     <string>Load a Scene &amp;from a Script File...</string>
    </property>
   </action>
-  <action name="action_Start_a_Session">
-   <property name="checkable">
-    <bool>true</bool>
-   </property>
-   <property name="text">
-    <string>&amp;Start a Session</string>
-   </property>
-   <property name="toolTip">
-    <string>Start a WebSocket Server to Share your Camera with Others on your Network.</string>
-   </property>
-  </action>
  </widget>
  <resources>
   <include location="Polyhedron_3.qrc"/>
diff --git a/Polyhedron/demo/Polyhedron/Plugins/AABB_tree/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/AABB_tree/CMakeLists.txt
index bff0df4c9a1..1336c086cd7 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/AABB_tree/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/AABB_tree/CMakeLists.txt
@@ -5,6 +5,6 @@ target_link_libraries(do_trees_intersect_plugin PUBLIC scene_surface_mesh_item s
 
 polyhedron_demo_plugin(cut_plugin Cut_plugin )
 target_link_libraries(cut_plugin PUBLIC scene_surface_mesh_item scene_basic_objects scene_color_ramp)
-if(TBB_FOUND)
-  CGAL_target_use_TBB(cut_plugin)
+if(TARGET CGAL::TBB_support)
+  target_link_libraries(cut_plugin PUBLIC CGAL::TBB_support)
 endif()
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Classification/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/Classification/CMakeLists.txt
index b4a49753ce2..288c22109ff 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Classification/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/Classification/CMakeLists.txt
@@ -1,54 +1,61 @@
 include( polyhedron_demo_macros )
 
-if(EIGEN3_FOUND)
+if(TARGET CGAL::Eigen_support)
 
   set(Classification_dependencies_met TRUE)
 
   find_package( Boost OPTIONAL_COMPONENTS serialization iostreams )
-  if (NOT Boost_SERIALIZATION_FOUND)
+  include(CGAL_Boost_serialization_support)
+  include(CGAL_Boost_iostreams_support)
+  if (NOT TARGET CGAL::Boost_serialization_support)
     message(STATUS "NOTICE: Boost Serialization not found. Classification plugin won't be available.")
     set(Classification_dependencies_met FALSE)
   endif()
 
-  if (NOT Boost_IOSTREAMS_FOUND)
+  if (NOT TARGET CGAL::Boost_iostreams_support)
     message(STATUS "NOTICE: Boost IOStreams not found. Classification plugin won't be available.")
     set(Classification_dependencies_met FALSE)
   endif()
 
   find_package(OpenCV QUIET COMPONENTS core ml) # Need core + machine learning
-  if (NOT OpenCV_FOUND)
+  include(CGAL_OpenCV_support)
+  if (NOT TARGET CGAL::OpenCV_support)
     message(STATUS "NOTICE: OpenCV was not found. OpenCV random forest predicate for classification won't be available.")
   endif()
 
   find_package(TensorFlow QUIET)
-  if (NOT TensorFlow_FOUND)
+  include(CGAL_TensorFlow_support)
+  if (NOT TARGET CGAL::TensorFlow_support)
     message(STATUS "NOTICE: TensorFlow not found, Neural Network predicate for classification won't be available.")
   endif()
 
   if (Classification_dependencies_met)
     qt5_wrap_ui( classificationUI_FILES Classification_widget.ui Classification_advanced_widget.ui )
     polyhedron_demo_plugin(classification_plugin Classification_plugin Point_set_item_classification Cluster_classification Surface_mesh_item_classification ${classificationUI_FILES} KEYWORDS Classification)
-    target_link_libraries(classification_plugin PUBLIC scene_points_with_normal_item
-      scene_polylines_item scene_polygon_soup_item scene_surface_mesh_item scene_selection_item scene_color_ramp)
+    target_link_libraries(classification_plugin PUBLIC
+      scene_points_with_normal_item
+      scene_polylines_item
+      scene_polygon_soup_item
+      scene_surface_mesh_item
+      scene_selection_item
+      scene_color_ramp
+      CGAL::Eigen_support
+      CGAL::Boost_serialization_support
+      CGAL::Boost_iostreams_support)
 
-    CGAL_target_use_Eigen(classification_plugin)
-    CGAL_target_use_Boost_IOStreams(classification_plugin)
-    CGAL_target_use_Boost_Serialization(classification_plugin)
     if(OpenCV_FOUND)
-      CGAL_target_use_OpenCV(classification_plugin)
+      target_link_libraries(classification_plugin PUBLIC CGAL::OpenCV_support)
     endif()
     if(TensorFlow_FOUND)
-      CGAL_target_use_TensorFlow(classification_plugin)
+      target_link_libraries(classification_plugin PUBLIC CGAL::TensorFlow_support)
     endif()
     if(TBB_FOUND)
-      CGAL_target_use_TBB(classification_plugin)
+      target_link_libraries(classification_plugin PUBLIC CGAL::TBB_support)
     endif()
 
     add_dependencies(classification_plugin point_set_selection_plugin selection_plugin)
   endif()
 
-else(EIGEN3_FOUND)
+else()
   message(STATUS "NOTICE: Eigen 3.1 (or greater) was not found. Classification plugin will not be available.")
 endif()
-
-
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Display/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/Display/CMakeLists.txt
index c783cd751ac..0f03d24021e 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Display/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/Display/CMakeLists.txt
@@ -1,7 +1,6 @@
 include( polyhedron_demo_macros )
-if(EIGEN3_FOUND)
+if(TARGET CGAL::Eigen_support)
   qt5_wrap_ui( display_propertyUI_FILES Display_property.ui )
   polyhedron_demo_plugin(display_property_plugin Display_property_plugin ${display_propertyUI_FILES})
-  target_link_libraries(display_property_plugin PUBLIC scene_surface_mesh_item scene_points_with_normal_item scene_color_ramp)
-  CGAL_target_use_Eigen(display_property_plugin)
-endif(EIGEN3_FOUND)
+  target_link_libraries(display_property_plugin PUBLIC scene_surface_mesh_item scene_points_with_normal_item scene_color_ramp CGAL::Eigen_support)
+endif()
diff --git a/Polyhedron/demo/Polyhedron/Plugins/IO/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/IO/CMakeLists.txt
index 7e6c6cdf4dc..b3a02fe105a 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/IO/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/IO/CMakeLists.txt
@@ -72,11 +72,10 @@ else()
   target_link_libraries(ply_plugin PUBLIC scene_points_with_normal_item scene_polygon_soup_item scene_surface_mesh_item scene_textured_item)
   target_compile_features(ply_plugin PRIVATE ${needed_cxx_features})
 
-  if (LASLIB_FOUND)
+  if (TARGET CGAL::LASLIB_support)
     polyhedron_demo_plugin(las_plugin LAS_io_plugin KEYWORDS IO PointSetProcessing Classification)
-    target_link_libraries(las_plugin PUBLIC scene_points_with_normal_item)
+    target_link_libraries(las_plugin PUBLIC scene_points_with_normal_item CGAL::LASLIB_support)
     target_compile_features(las_plugin PRIVATE ${needed_cxx_features})
-    CGAL_target_use_LASLIB(las_plugin)
   else()
     message(STATUS "NOTICE : the LAS IO plugin needs LAS libraries and will not be compiled.")
   endif()
diff --git a/Polyhedron/demo/Polyhedron/Plugins/IO/Implicit_function_io_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/IO/Implicit_function_io_plugin.cpp
index 1a02765e9f8..58f19006f7c 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/IO/Implicit_function_io_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/IO/Implicit_function_io_plugin.cpp
@@ -96,7 +96,7 @@ init(QMainWindow* mainWindow, CGAL::Three::Scene_interface* scene_interface, Mes
   QMenu* menu = menuFile->findChild<QMenu*>("menuGenerateObject");
   if(!menu){
     QAction* actionLoad = mw->findChild<QAction*>("actionLoadPlugin");
-    menu = new QMenu(tr("Generate &Objet"), menuFile);
+    menu = new QMenu(tr("Generate &Object"), menuFile);
     menu->setObjectName("menuGenerateObject");
     menuFile->insertMenu(actionLoad, menu);
   }
diff --git a/Polyhedron/demo/Polyhedron/Plugins/IO/VTK_io_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/IO/VTK_io_plugin.cpp
index 272aa7500bd..7dbc3eaa910 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/IO/VTK_io_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/IO/VTK_io_plugin.cpp
@@ -376,8 +376,8 @@ public:
 
     if (is_c3t3)
     {
-      typedef boost::array<int, 3> Facet; // 3 = id
-      typedef boost::array<int, 5> Tet_with_ref; // first 4 = id, fifth = reference
+      typedef std::array<int, 3> Facet; // 3 = id
+      typedef std::array<int, 5> Tet_with_ref; // first 4 = id, fifth = reference
       Scene_c3t3_item* c3t3_item = new Scene_c3t3_item();
       c3t3_item->set_valid(false);
       //build a triangulation from data:
@@ -420,7 +420,9 @@ public:
           std::swap(finite_cells[i][1], finite_cells[i][3]);
         }
       }
-      CGAL::build_triangulation<Tr, true>(c3t3_item->c3t3().triangulation(), points, finite_cells, border_facets);
+      std::vector<typename Tr::Vertex_handle> new_vertices;
+      CGAL::build_triangulation<Tr, true>(c3t3_item->c3t3().triangulation(),
+        points, finite_cells, border_facets, new_vertices);
 
       for( C3t3::Triangulation::Finite_cells_iterator
            cit = c3t3_item->c3t3().triangulation().finite_cells_begin();
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/C3t3_io_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/C3t3_io_plugin.cpp
index d2232c11dd4..8b708c059f2 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/C3t3_io_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/C3t3_io_plugin.cpp
@@ -135,7 +135,8 @@ Polyhedron_demo_c3t3_binary_io_plugin::load(
              ++cit)
         {
             CGAL_assertion(cit->info() >= 0);
-            item->c3t3().add_to_complex(cit, cit->info());
+            if(cit->info() != 0)
+              item->c3t3().add_to_complex(cit, cit->info());
             for(int i=0; i < 4; ++i)
             {
               if(cit->surface_patch_index(i)>0)
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/CMakeLists.txt
index 274464901df..2e819fa7124 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/Mesh_3/CMakeLists.txt
@@ -54,9 +54,10 @@ target_link_libraries(mesh_3_optimization_plugin PUBLIC scene_c3t3_item scene_su
 
 # Use Eigen
  find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
+ include(CGAL_Eigen_support)
 
- if (EIGEN3_FOUND)
-   CGAL_target_use_Eigen(mesh_3_optimization_plugin)
+ if (TARGET CGAL::Eigen_support)
+   target_link_libraries(mesh_3_optimization_plugin PUBLIC CGAL::Eigen_support)
  else() #eigen
    message(STATUS "The Mesh_3_optimization_plugin requires Eigen, which was not found, and will use a deprecated class to replace it. Warnings are to be expected.")
  endif()#eigen
@@ -69,8 +70,8 @@ polyhedron_demo_plugin(c3t3_rib_exporter_plugin C3t3_rib_exporter_plugin ${ribUI
 target_link_libraries(c3t3_rib_exporter_plugin PUBLIC scene_c3t3_item)
 
 if(TBB_FOUND)
-  CGAL_target_use_TBB(mesh_3_plugin)
-  CGAL_target_use_TBB(mesh_3_optimization_plugin)
-  CGAL_target_use_TBB(c3t3_io_plugin)
-  CGAL_target_use_TBB(c3t3_rib_exporter_plugin)
+  target_link_libraries(mesh_3_plugin PUBLIC CGAL::TBB_support)
+  target_link_libraries(mesh_3_optimization_plugin PUBLIC CGAL::TBB_support)
+  target_link_libraries(c3t3_io_plugin PUBLIC CGAL::TBB_support)
+  target_link_libraries(c3t3_rib_exporter_plugin PUBLIC CGAL::TBB_support)
 endif()
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/PartitionDialog.ui b/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/PartitionDialog.ui
index 1c939c87a9c..91f3b989f8a 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/PartitionDialog.ui
+++ b/Polyhedron/demo/Polyhedron/Plugins/Operations_on_polyhedra/PartitionDialog.ui
@@ -67,7 +67,7 @@
 p, li { white-space: pre-wrap; }
 &lt;/style&gt;&lt;/head&gt;&lt;body style=&quot; font-family:'Sans Serif'; font-size:9pt; font-weight:400; font-style:normal;&quot;&gt;
 &lt;p style=&quot; margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;&quot;&gt;Tip: To split your mesh according to the result of this operation, you can click on &lt;/p&gt;
-&lt;p style=&quot; margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;&quot;&gt;&lt;span style=&quot; font-weight:600;&quot;&gt;Operations-&amp;gt;Operations on Polyhedra-&amp;gt;Split Selected Polyhedra&lt;/span&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
+&lt;p style=&quot; margin-top:12px; margin-bottom:12px; margin-left:0px; margin-right:0px; -qt-block-indent:0; text-indent:0px;&quot;&gt;&lt;span style=&quot; font-weight:600;&quot;&gt;Operations-&amp;gt;Polygon Mesh Processing-&amp;gt;Split Selected Polyhedra&lt;/span&gt;&lt;/p&gt;&lt;/body&gt;&lt;/html&gt;</string>
      </property>
     </widget>
    </item>
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp
index 184770f685b..4215c75421b 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PCA/Basic_generator_plugin.cpp
@@ -59,7 +59,7 @@ public :
     QMenu* menu = menuFile->findChild<QMenu*>("menuGenerateObject");
     if(!menu){
       QAction* actionLoad = mw->findChild<QAction*>("actionLoadPlugin");
-      menu = new QMenu(tr("Generate &Objet"), menuFile);
+      menu = new QMenu(tr("Generate &Object"), menuFile);
       menu->setObjectName("menuGenerateObject");
       menuFile->insertMenu(actionLoad, menu);
     }
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/PMP/CMakeLists.txt
index f5380d67133..56d43cccef3 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/CMakeLists.txt
@@ -1,33 +1,29 @@
 include( polyhedron_demo_macros )
-if(EIGEN3_FOUND)
+if(TARGET CGAL::Eigen_support)
 
   polyhedron_demo_plugin(jet_fitting_plugin Jet_fitting_plugin)
-  target_link_libraries(jet_fitting_plugin PUBLIC scene_surface_mesh_item scene_polylines_item)
-  CGAL_target_use_Eigen(jet_fitting_plugin)
+  target_link_libraries(jet_fitting_plugin PUBLIC scene_surface_mesh_item scene_polylines_item CGAL::Eigen_support)
 
-else(EIGEN3_FOUND)
+else()
   message(STATUS "NOTICE: Eigen 3.1 (or greater) was not found. Jet fitting plugin will not be available.")
-endif(EIGEN3_FOUND)
+endif()
 
 polyhedron_demo_plugin(extrude_plugin Extrude_plugin KEYWORDS PMP)
 target_link_libraries(extrude_plugin PUBLIC scene_surface_mesh_item scene_selection_item)
 
-if(EIGEN3_FOUND)
+if(TARGET CGAL::Eigen_support)
   if("${EIGEN3_VERSION}" VERSION_GREATER "3.1.90")
 
     qt5_wrap_ui( hole_fillingUI_FILES Hole_filling_widget.ui)
     polyhedron_demo_plugin(hole_filling_plugin Hole_filling_plugin ${hole_fillingUI_FILES} KEYWORDS PMP)
-    target_link_libraries(hole_filling_plugin PUBLIC scene_surface_mesh_item scene_polylines_item scene_selection_item)
-    CGAL_target_use_Eigen(hole_filling_plugin)
+    target_link_libraries(hole_filling_plugin PUBLIC scene_surface_mesh_item scene_polylines_item scene_selection_item CGAL::Eigen_support)
 
     qt5_wrap_ui( fairingUI_FILES Fairing_widget.ui)
     polyhedron_demo_plugin(fairing_plugin Fairing_plugin ${fairingUI_FILES} KEYWORDS PMP)
-    target_link_libraries(fairing_plugin PUBLIC scene_selection_item)
-    CGAL_target_use_Eigen(fairing_plugin)
+    target_link_libraries(fairing_plugin PUBLIC scene_selection_item CGAL::Eigen_support)
 
     polyhedron_demo_plugin(hole_filling_polyline_plugin Hole_filling_polyline_plugin )
-    target_link_libraries(hole_filling_polyline_plugin PUBLIC scene_surface_mesh_item scene_polylines_item)
-    CGAL_target_use_Eigen(hole_filling_polyline_plugin)
+    target_link_libraries(hole_filling_polyline_plugin PUBLIC scene_surface_mesh_item scene_polylines_item CGAL::Eigen_support)
 
     qt5_wrap_ui( Mean_curvature_flow_skeleton_pluginUI_FILES  Mean_curvature_flow_skeleton_plugin.ui)
     polyhedron_demo_plugin(mean_curvature_flow_skeleton_plugin Mean_curvature_flow_skeleton_plugin ${Mean_curvature_flow_skeleton_pluginUI_FILES})
@@ -37,20 +33,19 @@ if(EIGEN3_FOUND)
         scene_points_with_normal_item
         scene_polylines_item
         scene_mcf_item
-        demo_framework)
-      CGAL_target_use_Eigen(mean_curvature_flow_skeleton_plugin)
+        demo_framework
+        CGAL::Eigen_support)
       # The smoothing plugin can still do some things, even if Ceres is not found
       qt5_wrap_ui( smoothingUI_FILES Smoothing_plugin.ui)
       polyhedron_demo_plugin(smoothing_plugin Smoothing_plugin ${smoothingUI_FILES})
-      target_link_libraries(smoothing_plugin PUBLIC scene_surface_mesh_item scene_selection_item)
-      CGAL_target_use_Eigen(smoothing_plugin)
+      target_link_libraries(smoothing_plugin PUBLIC scene_surface_mesh_item scene_selection_item CGAL::Eigen_support)
       find_package(Ceres QUIET)
       if(TARGET ceres)
         target_compile_definitions( smoothing_plugin PRIVATE CGAL_PMP_USE_CERES_SOLVER )
         target_link_libraries(smoothing_plugin PUBLIC ceres)
       endif()
 
-      CGAL_target_use_Eigen(extrude_plugin)
+      target_link_libraries(extrude_plugin PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "NOTICE: The hole filling and fairing plugins require Eigen 3.2 (or higher) and will not be available.")
   endif()
@@ -106,17 +101,16 @@ qt5_wrap_ui( isotropicRemeshingUI_FILES Isotropic_remeshing_dialog.ui)
 polyhedron_demo_plugin(isotropic_remeshing_plugin Isotropic_remeshing_plugin  ${isotropicRemeshingUI_FILES} KEYWORDS PMP)
 target_link_libraries(isotropic_remeshing_plugin PUBLIC scene_surface_mesh_item scene_selection_item)
 
-if(TBB_FOUND)
-  CGAL_target_use_TBB(isotropic_remeshing_plugin)
+if(TARGET CGAL::TBB_support)
+  target_link_libraries(isotropic_remeshing_plugin PUBLIC CGAL::TBB_support)
 endif()
 
 polyhedron_demo_plugin(distance_plugin Distance_plugin KEYWORDS PMP)
 target_link_libraries(distance_plugin PUBLIC scene_surface_mesh_item  scene_color_ramp)
-if(TBB_FOUND)
-  CGAL_target_use_TBB(distance_plugin)
+if(TARGET CGAL::TBB_support)
+  target_link_libraries(distance_plugin PUBLIC CGAL::TBB_support)
 endif()
 
-
 polyhedron_demo_plugin(detect_sharp_edges_plugin Detect_sharp_edges_plugin KEYWORDS IO Mesh_3 PMP)
 target_link_libraries(detect_sharp_edges_plugin PUBLIC scene_surface_mesh_item)
 
@@ -130,4 +124,3 @@ target_link_libraries(degenerated_faces_plugin PUBLIC scene_surface_mesh_item sc
 qt5_wrap_ui( engravUI_FILES Engrave_dock_widget.ui )
 polyhedron_demo_plugin(engrave_text_plugin Engrave_text_plugin ${engravUI_FILES})
 target_link_libraries(engrave_text_plugin PUBLIC scene_surface_mesh_item scene_selection_item scene_polylines_item)
-
diff --git a/Polyhedron/demo/Polyhedron/Plugins/PMP/Distance_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/PMP/Distance_plugin.cpp
index 587e34051c9..031ac458e76 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/PMP/Distance_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/PMP/Distance_plugin.cpp
@@ -34,6 +34,7 @@ typedef Scene_surface_mesh_item Scene_face_graph_item;
 typedef Scene_face_graph_item::Face_graph Face_graph;
 
 #if defined(CGAL_LINKED_WITH_TBB)
+#include <tbb/parallel_for.h>
 template <class AABB_tree, class Point_3>
 struct Distance_computation{
   const AABB_tree& tree;
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Point_set/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/Point_set/CMakeLists.txt
index d29ca1cf7b8..a1ec1dec229 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Point_set/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/Point_set/CMakeLists.txt
@@ -1,65 +1,63 @@
 include( polyhedron_demo_macros )
-if(EIGEN3_FOUND)
+if(TARGET CGAL::Eigen_support)
 
   find_package(SCIP QUIET)
-  if(NOT SCIP_FOUND)
+  include(CGAL_SCIP_support)
+  if(NOT TARGET CGAL::SCIP_support)
     find_package(GLPK QUIET)
+    include(CGAL_GLPK_support)
   endif()
 
-  if(NOT SCIP_FOUND AND NOT GLPK_FOUND)
+  if(NOT TARGET CGAL::SCIP_support AND NOT TARGET CGAL::GLPK_support)
     message(STATUS "NOTICE: SCIP and GLPK were not found. Polygonal surface reconstruction will not be available.")
   endif()
 
   qt5_wrap_ui( surface_reconstructionUI_FILES Surface_reconstruction_plugin.ui)
   polyhedron_demo_plugin(surface_reconstruction_plugin Surface_reconstruction_plugin Surface_reconstruction_poisson_impl Surface_reconstruction_advancing_front_impl Surface_reconstruction_scale_space_impl Surface_reconstruction_polygonal_impl ${surface_reconstructionUI_FILES} KEYWORDS PointSetProcessing)
-  target_link_libraries(surface_reconstruction_plugin PUBLIC scene_polygon_soup_item scene_surface_mesh_item scene_points_with_normal_item)
-  CGAL_target_use_Eigen(surface_reconstruction_plugin)
+  target_link_libraries(surface_reconstruction_plugin PUBLIC scene_polygon_soup_item scene_surface_mesh_item scene_points_with_normal_item CGAL::Eigen_support)
 
-  if (SCIP_FOUND)
-    CGAL_target_use_SCIP(surface_reconstruction_plugin)
-  elseif(GLPK_FOUND)
-    CGAL_target_use_GLPK(surface_reconstruction_plugin)
+  if (TARGET CGAL::SCIP_support)
+    target_link_libraries(surface_reconstruction_plugin PUBLIC CGAL::SCIP_support)
+  elseif(TARGET CGAL::GLPK_support)
+    target_link_libraries(surface_reconstruction_plugin PUBLIC CGAL::GLPK_support)
   endif()
 
   qt5_wrap_ui( point_set_normal_estimationUI_FILES Point_set_normal_estimation_plugin.ui)
   polyhedron_demo_plugin(point_set_normal_estimation_plugin Point_set_normal_estimation_plugin ${point_set_normal_estimationUI_FILES} KEYWORDS PointSetProcessing Classification)
-  target_link_libraries(point_set_normal_estimation_plugin PUBLIC scene_points_with_normal_item scene_callback_signaler)
-  CGAL_target_use_Eigen(point_set_normal_estimation_plugin)
+  target_link_libraries(point_set_normal_estimation_plugin PUBLIC scene_points_with_normal_item scene_callback_signaler CGAL::Eigen_support)
 
   qt5_wrap_ui( features_detection_pluginUI_FILES Features_detection_plugin.ui)
   polyhedron_demo_plugin(features_detection_plugin Features_detection_plugin ${features_detection_pluginUI_FILES} KEYWORDS PointSetProcessing)
-  target_link_libraries(features_detection_plugin PUBLIC scene_points_with_normal_item)
-  CGAL_target_use_Eigen(features_detection_plugin)
+  target_link_libraries(features_detection_plugin PUBLIC scene_points_with_normal_item CGAL::Eigen_support)
 
   polyhedron_demo_plugin(point_set_smoothing_plugin Point_set_smoothing_plugin KEYWORDS PointSetProcessing)
-  target_link_libraries(point_set_smoothing_plugin PUBLIC scene_points_with_normal_item scene_callback_signaler)
-  CGAL_target_use_Eigen(point_set_smoothing_plugin)
+  target_link_libraries(point_set_smoothing_plugin PUBLIC scene_points_with_normal_item scene_callback_signaler CGAL::Eigen_support)
 
   polyhedron_demo_plugin(point_set_average_spacing_plugin Point_set_average_spacing_plugin KEYWORDS PointSetProcessing Classification)
-  target_link_libraries(point_set_average_spacing_plugin PUBLIC scene_points_with_normal_item scene_callback_signaler)
-  CGAL_target_use_Eigen(point_set_average_spacing_plugin)
+  target_link_libraries(point_set_average_spacing_plugin PUBLIC scene_points_with_normal_item scene_callback_signaler CGAL::Eigen_support)
 
   qt5_wrap_ui(point_set_shape_detectionUI_FILES Point_set_shape_detection_plugin.ui)
   polyhedron_demo_plugin(point_set_shape_detection_plugin Point_set_shape_detection_plugin ${point_set_shape_detectionUI_FILES} KEYWORDS PointSetProcessing Classification)
-  target_link_libraries(point_set_shape_detection_plugin PUBLIC scene_surface_mesh_item scene_points_with_normal_item scene_polygon_soup_item scene_callback_signaler)
-  CGAL_target_use_Eigen(point_set_shape_detection_plugin)
+  target_link_libraries(point_set_shape_detection_plugin PUBLIC scene_surface_mesh_item scene_points_with_normal_item scene_polygon_soup_item scene_callback_signaler CGAL::Eigen_support)
 
   find_package(OpenGR QUIET)
+  include(CGAL_OpenGR_support)
   find_package(libpointmatcher QUIET)
+  include(CGAL_pointmatcher_support)
 
-  if (OpenGR_FOUND OR libpointmatcher_FOUND)
+  if (TARGET CGAL::OpenGR_support OR CGAL::pointmatcher_support)
     qt5_wrap_ui(register_point_setsUI_FILES Register_point_sets_plugin.ui)
     polyhedron_demo_plugin(register_point_sets_plugin Register_point_sets_plugin ${register_point_setsUI_FILES} KEYWORDS PointSetProcessing)
     target_link_libraries(register_point_sets_plugin PUBLIC scene_points_with_normal_item)
-    CGAL_target_use_Eigen(register_point_sets_plugin)
-    if (OpenGR_FOUND)
-      CGAL_target_use_OpenGR(register_point_sets_plugin)
+    target_link_libraries(register_point_sets_plugin PUBLIC CGAL::Eigen_support)
+    if (TARGET CGAL::OpenGR_support)
+      target_link_libraries(register_point_sets_plugin PUBLIC CGAL::OpenGR_support)
     endif()
-    if (libpointmatcher_FOUND)
-      CGAL_target_use_pointmatcher(register_point_sets_plugin)
+    if (TARGET CGAL::pointmatcher_support)
+      target_link_libraries(register_point_sets_plugin PUBLIC CGAL::pointmatcher_support)
     endif()
   else()
-    message(STATUS "NOTICE: OpenGR and libpointmatcher were not found. Registrationp plugin will not be available.")
+    message(STATUS "NOTICE: OpenGR and libpointmatcher were not found. Registration plugin will not be available.")
   endif()
 
 else(EIGEN3_FOUND)
@@ -111,7 +109,7 @@ endif()
   polyhedron_demo_plugin(point_set_to_mesh_distance_plugin Point_set_to_mesh_distance_plugin ${distanceUI_FILES} KEYWORDS PointSetProcessing)
   target_link_libraries(point_set_to_mesh_distance_plugin PUBLIC scene_points_with_normal_item scene_surface_mesh_item scene_color_ramp)
 
-  if(TBB_FOUND)
+  if(TARGET CGAL::TBB_support)
     foreach(plugin
         surface_reconstruction_plugin
         point_set_normal_estimation_plugin
@@ -130,7 +128,7 @@ endif()
         alpha_shape_plugin
         point_set_to_mesh_distance_plugin)
       if(TARGET ${plugin})
-        CGAL_target_use_TBB(${plugin})
+        target_link_libraries(${plugin} PUBLIC CGAL::TBB_support)
       endif()
     endforeach()
   endif()
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Point_set/Point_set_outliers_removal_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Point_set/Point_set_outliers_removal_plugin.cpp
index f5a217a91c9..c79b878dd32 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Point_set/Point_set_outliers_removal_plugin.cpp
+++ b/Polyhedron/demo/Polyhedron/Plugins/Point_set/Point_set_outliers_removal_plugin.cpp
@@ -40,12 +40,13 @@ struct Outlier_removal_functor
   {
     // Computes outliers
     *result =
-      CGAL::remove_outliers(*points,
-                            nb_neighbors,
-                            points->parameters().
-                            threshold_percent(removed_percentage).
-                            threshold_distance(distance_threshold).
-                            callback (*(this->callback())));
+      CGAL::remove_outliers<CGAL::Parallel_if_available_tag>
+      (*points,
+       nb_neighbors,
+       points->parameters().
+       threshold_percent(removed_percentage).
+       threshold_distance(distance_threshold).
+       callback (*(this->callback())));
   }
 };
 
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/CMakeLists.txt
index d56331772af..45c1eccb50e 100644
--- a/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/CMakeLists.txt
+++ b/Polyhedron/demo/Polyhedron/Plugins/Surface_mesh/CMakeLists.txt
@@ -4,18 +4,17 @@ if(POLICY CMP0074)
   cmake_policy(SET CMP0074 NEW)
 endif()
 
-if(EIGEN3_FOUND)
+if(TARGET CGAL::Eigen_support)
   find_package(CGAL COMPONENTS Core)
 
   include(${CGAL_USE_FILE})
 
   qt5_wrap_ui(parameterizationUI_FILES Parameterization_widget.ui OTE_dialog.ui)
   polyhedron_demo_plugin(parameterization_plugin Parameterization_plugin ${parameterizationUI_FILES})
-  target_link_libraries(parameterization_plugin PUBLIC scene_surface_mesh_item scene_textured_item scene_selection_item)
-  CGAL_target_use_Eigen(parameterization_plugin)
-else(EIGEN3_FOUND)
+  target_link_libraries(parameterization_plugin PUBLIC scene_surface_mesh_item scene_textured_item scene_selection_item CGAL::Eigen_support)
+else()
   message(STATUS "NOTICE: Eigen 3.1 (or greater) was not found. The Parameterization plugin will not be available.")
-endif(EIGEN3_FOUND)
+endif()
 
 qt5_wrap_ui( segmentationUI_FILES Mesh_segmentation_widget.ui)
 polyhedron_demo_plugin(mesh_segmentation_plugin Mesh_segmentation_plugin ${segmentationUI_FILES})
@@ -32,11 +31,11 @@ target_link_libraries(mesh_simplification_plugin PUBLIC scene_surface_mesh_item
 qt5_wrap_ui( remeshingUI_FILES  Remeshing_dialog.ui)
 polyhedron_demo_plugin(offset_meshing_plugin Offset_meshing_plugin ${remeshingUI_FILES})
 target_link_libraries(offset_meshing_plugin PUBLIC scene_surface_mesh_item scene_polygon_soup_item)
-if(EIGEN3_FOUND)
-  CGAL_target_use_Eigen(offset_meshing_plugin)
+if(TARGET CGAL::Eigen_support)
+  target_link_libraries(offset_meshing_plugin PUBLIC CGAL::Eigen_support)
 endif()
-if(TBB_FOUND)
-  CGAL_target_use_TBB(offset_meshing_plugin)
+if(TARGET CGAL::TBB_support)
+  target_link_libraries(offset_meshing_plugin PUBLIC CGAL::TBB_support)
 endif()
 
 qt5_wrap_ui( shortestPathUI_FILES Shortest_path_widget.ui )
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/CMakeLists.txt b/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/CMakeLists.txt
new file mode 100644
index 00000000000..6b018456711
--- /dev/null
+++ b/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/CMakeLists.txt
@@ -0,0 +1,12 @@
+include( polyhedron_demo_macros )
+
+remove_definitions(-DQT_STATICPLUGIN)
+
+qt5_wrap_cpp( VOLUME_MOC_OUTFILES ${CMAKE_CURRENT_SOURCE_DIR}/Volume_plane_thread.h )
+qt5_wrap_cpp( VOLUME_MOC_OUTFILES ${CMAKE_CURRENT_SOURCE_DIR}/Volume_plane_interface.h )
+
+qt5_wrap_ui( tetRemeshingUI_FILES  Tetrahedral_remeshing_dialog.ui)
+polyhedron_demo_plugin(tetrahedral_remeshing_plugin Tetrahedral_remeshing_plugin ${tetRemeshingUI_FILES}
+                       KEYWORDS Tetrahedral_remeshing)
+target_link_libraries(tetrahedral_remeshing_plugin
+                                  PUBLIC scene_c3t3_item ${OPENGL_gl_LIBRARY})
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/Tetrahedral_remeshing_dialog.ui b/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/Tetrahedral_remeshing_dialog.ui
new file mode 100644
index 00000000000..351de08c508
--- /dev/null
+++ b/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/Tetrahedral_remeshing_dialog.ui
@@ -0,0 +1,210 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ui version="4.0">
+ <class>Tetrahedral_remeshing_dialog</class>
+ <widget class="QDialog" name="Tetrahedral_remeshing_dialog">
+  <property name="enabled">
+   <bool>true</bool>
+  </property>
+  <property name="geometry">
+   <rect>
+    <x>0</x>
+    <y>0</y>
+    <width>376</width>
+    <height>259</height>
+   </rect>
+  </property>
+  <property name="windowTitle">
+   <string>Isotropic remeshing criteria</string>
+  </property>
+  <layout class="QVBoxLayout" name="verticalLayout">
+   <item>
+    <widget class="QLabel" name="objectName">
+     <property name="font">
+      <font>
+       <pointsize>15</pointsize>
+       <weight>75</weight>
+       <bold>true</bold>
+      </font>
+     </property>
+     <property name="text">
+      <string>NO OBJECT</string>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QLabel" name="objectNameSize">
+     <property name="text">
+      <string>No size</string>
+     </property>
+    </widget>
+   </item>
+   <item>
+    <widget class="QGroupBox" name="groupBox">
+     <property name="title">
+      <string>Tetrahedral remeshing</string>
+     </property>
+     <layout class="QGridLayout" name="gridLayout_2" rowstretch="0,0,0,0" columnstretch="0,0">
+      <item row="3" column="0">
+       <widget class="QLabel" name="protect_label">
+        <property name="text">
+         <string>Protect boundaries</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+       </widget>
+      </item>
+      <item row="1" column="1">
+       <widget class="QSpinBox" name="nbIterations_spinbox">
+        <property name="minimumSize">
+         <size>
+          <width>110</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="value">
+         <number>1</number>
+        </property>
+       </widget>
+      </item>
+      <item row="3" column="1">
+       <widget class="QCheckBox" name="protect_checkbox">
+        <property name="text">
+         <string/>
+        </property>
+        <property name="checked">
+         <bool>false</bool>
+        </property>
+       </widget>
+      </item>
+      <item row="2" column="0">
+       <spacer name="verticalSpacer_3">
+        <property name="orientation">
+         <enum>Qt::Vertical</enum>
+        </property>
+        <property name="sizeType">
+         <enum>QSizePolicy::Maximum</enum>
+        </property>
+        <property name="sizeHint" stdset="0">
+         <size>
+          <width>20</width>
+          <height>40</height>
+         </size>
+        </property>
+       </spacer>
+      </item>
+      <item row="1" column="0">
+       <widget class="QLabel" name="nbIterations_label">
+        <property name="text">
+         <string>Number of Main iterations</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+        <property name="buddy">
+         <cstring>nbIterations_spinbox</cstring>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="0">
+       <widget class="QLabel" name="edgeLength_label">
+        <property name="text">
+         <string>Target edge length</string>
+        </property>
+        <property name="alignment">
+         <set>Qt::AlignRight|Qt::AlignTrailing|Qt::AlignVCenter</set>
+        </property>
+        <property name="buddy">
+         <cstring>edgeLength_dspinbox</cstring>
+        </property>
+       </widget>
+      </item>
+      <item row="0" column="1">
+       <widget class="QDoubleSpinBox" name="edgeLength_dspinbox">
+        <property name="minimumSize">
+         <size>
+          <width>110</width>
+          <height>0</height>
+         </size>
+        </property>
+        <property name="maximum">
+         <double>1000.000000000000000</double>
+        </property>
+        <property name="singleStep">
+         <double>0.100000000000000</double>
+        </property>
+       </widget>
+      </item>
+     </layout>
+    </widget>
+   </item>
+   <item>
+    <spacer name="verticalSpacer_2">
+     <property name="orientation">
+      <enum>Qt::Vertical</enum>
+     </property>
+     <property name="sizeType">
+      <enum>QSizePolicy::MinimumExpanding</enum>
+     </property>
+     <property name="sizeHint" stdset="0">
+      <size>
+       <width>0</width>
+       <height>0</height>
+      </size>
+     </property>
+    </spacer>
+   </item>
+   <item>
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
+     </property>
+    </widget>
+   </item>
+  </layout>
+ </widget>
+ <tabstops>
+  <tabstop>edgeLength_dspinbox</tabstop>
+  <tabstop>nbIterations_spinbox</tabstop>
+  <tabstop>protect_checkbox</tabstop>
+  <tabstop>buttonBox</tabstop>
+ </tabstops>
+ <resources/>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>accepted()</signal>
+   <receiver>Tetrahedral_remeshing_dialog</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>397</x>
+     <y>333</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>157</x>
+     <y>195</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>rejected()</signal>
+   <receiver>Tetrahedral_remeshing_dialog</receiver>
+   <slot>reject()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>397</x>
+     <y>333</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>286</x>
+     <y>195</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
+</ui>
diff --git a/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/Tetrahedral_remeshing_plugin.cpp b/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/Tetrahedral_remeshing_plugin.cpp
new file mode 100644
index 00000000000..bbf5dc24de6
--- /dev/null
+++ b/Polyhedron/demo/Polyhedron/Plugins/Tetrahedral_remeshing/Tetrahedral_remeshing_plugin.cpp
@@ -0,0 +1,217 @@
+#define CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+//#define CGAL_DUMP_REMESHING_STEPS
+//#define CGAL_TETRAHEDRAL_REMESHING_DEBUG
+//#define CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS
+//#define CGAL_TETRAHEDRAL_REMESHING_PROFILE
+//#define CGAL_TETRAHEDRAL_REMESHING_SMOOTH_SHARP_EDGES
+
+#include <QtCore/qglobal.h>
+
+#include <CGAL/Three/Polyhedron_demo_plugin_interface.h>
+
+#include "Scene_c3t3_item.h"
+#include "C3t3_type.h"
+
+#include <CGAL/tetrahedral_remeshing.h>
+
+#include <unordered_map>
+#include <memory>
+
+#include <QElapsedTimer>
+#include <QAction>
+#include <QMainWindow>
+#include <QApplication>
+#include <QString>
+#include <QInputDialog>
+#include <QtPlugin>
+#include <QMessageBox>
+
+#include "ui_Tetrahedral_remeshing_dialog.h"
+
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+std::size_t nb_topology_test = 0;
+std::size_t nb_impossible = 0;
+std::size_t nb_valid_collapse = 0;
+std::size_t nb_invalid_collapse = 0;
+std::size_t nb_invalid_lengths = 0;
+std::size_t nb_invalid_collapse_short = 0;
+std::size_t nb_orientation_v0 = 0;
+std::size_t nb_orientation_v1 = 0;
+std::size_t nb_orientation_midpoint = 0;
+std::size_t nb_test_v0 = 0;
+std::size_t nb_test_v1 = 0;
+std::size_t nb_test_midpoint = 0;
+#endif
+
+using namespace CGAL::Three;
+class Polyhedron_demo_tetrahedral_remeshing_plugin :
+  public QObject,
+  public Polyhedron_demo_plugin_interface
+{
+  Q_OBJECT
+  Q_INTERFACES(CGAL::Three::Polyhedron_demo_plugin_interface)
+  Q_PLUGIN_METADATA(IID "com.geometryfactory.PolyhedronDemo.PluginInterface/1.0" FILE "tetrahedral_remeshing_plugin.json")
+
+public:
+  void init(QMainWindow* mainWindow, Scene_interface* scene_interface, Messages_interface*)
+  {
+    this->scene = scene_interface;
+    this->mw = mainWindow;
+
+    actionTetrahedralRemeshing_ = new QAction("Tetrahedral Remeshing", mw);
+    if (actionTetrahedralRemeshing_) {
+      connect(actionTetrahedralRemeshing_, SIGNAL(triggered()),
+        this, SLOT(tetrahedral_remeshing()));
+    }
+  }
+
+  QList<QAction*> actions() const {
+    return QList<QAction*>() << actionTetrahedralRemeshing_;
+  }
+
+  bool applicable(QAction*) const
+  {
+    return qobject_cast<Scene_c3t3_item*>(scene->item(scene->mainSelectionIndex()));
+  }
+
+public Q_SLOTS:
+  void tetrahedral_remeshing()
+  {
+    const Scene_interface::Item_id index = scene->mainSelectionIndex();
+
+    Scene_c3t3_item* c3t3_item =
+      qobject_cast<Scene_c3t3_item*>(scene->item(index));
+
+    if (c3t3_item)
+    {
+      // Create dialog box
+      QDialog dialog(mw);
+      Ui::Tetrahedral_remeshing_dialog ui
+        = tet_remeshing_dialog(&dialog, c3t3_item);
+
+      // Get values
+      int i = dialog.exec();
+      if (i == QDialog::Rejected)
+      {
+        std::cout << "Remeshing aborted" << std::endl;
+        return;
+      }
+      double target_length = ui.edgeLength_dspinbox->value();
+      unsigned int nb_iter = ui.nbIterations_spinbox->value();
+      bool protect = ui.protect_checkbox->isChecked();
+
+      // wait cursor
+      QApplication::setOverrideCursor(Qt::WaitCursor);
+
+      QElapsedTimer time;
+      time.start();
+
+      CGAL::tetrahedral_isotropic_remeshing(
+          c3t3_item->c3t3(),
+          target_length,
+          CGAL::parameters::remesh_boundaries(!protect)
+          .number_of_iterations(nb_iter));
+
+      std::cout << "Remeshing done (" << time.elapsed() << " ms)" << std::endl;
+
+      c3t3_item->invalidateOpenGLBuffers();
+      c3t3_item->c3t3_changed();
+      this->scene->itemChanged(index);
+
+      // default cursor
+      QApplication::restoreOverrideCursor();
+
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+      std::cout << "nb_topology_test = " << nb_topology_test << std::endl;
+      std::cout << "nb_impossible = " << nb_impossible << std::endl;
+
+      std::cout << "nb_invalid_collapse_short = " << nb_invalid_collapse_short << std::endl;
+
+      std::cout << "nb_orientation_fail_v0 = " << nb_orientation_v0 << std::endl;
+      std::cout << "nb_orientation_fail_v1 = " << nb_orientation_v1 << std::endl;
+      std::cout << "nb_orientation_fail_midpoint = " << nb_orientation_midpoint << std::endl;
+
+      std::cout << "nb_test_v0 = " << nb_test_v0 << std::endl;
+      std::cout << "nb_test_v1 = " << nb_test_v1 << std::endl;
+      std::cout << "nb_test_midpoint = " << nb_test_midpoint << std::endl;
+      std::cout << std::endl;
+
+      if (nb_test_v0 > 0)
+        std::cout << "nb_orientation_v0 / nb_test_v0  = "
+        << ((float)nb_orientation_v0 / (float)nb_test_v0) << std::endl;
+      if (nb_test_v1 > 1)
+        std::cout << "nb_orientation_v1 / nb_test_v1  = "
+        << ((float)nb_orientation_v1 / (float)nb_test_v1) << std::endl;
+      if (nb_test_midpoint > 0)
+        std::cout << "nb_orientation_midpoint / nb_test_midpoint  = "
+        << ((float)nb_orientation_midpoint / (float)nb_test_midpoint) << std::endl;
+
+      std::cout << std::endl;
+      std::cout << "nb_valid_collapse = " << nb_valid_collapse << std::endl;
+      std::cout << "nb_invalid_collapse = " << nb_invalid_collapse << std::endl;
+      std::cout << "nb_invalid_lengths = " << nb_invalid_lengths << std::endl;
+#endif
+    }
+    else
+    {
+      std::cout << "Can't remesh that type of thing" << std::endl;
+    }
+  }
+
+private:
+  Scene_interface *scene;
+  QMainWindow* mw;
+
+  Ui::Tetrahedral_remeshing_dialog
+  tet_remeshing_dialog(QDialog* dialog,
+                       Scene_c3t3_item* c3t3_item)
+  {
+    Ui::Tetrahedral_remeshing_dialog ui;
+    ui.setupUi(dialog);
+    connect(ui.buttonBox, SIGNAL(accepted()), dialog, SLOT(accept()));
+    connect(ui.buttonBox, SIGNAL(rejected()), dialog, SLOT(reject()));
+
+    //Set default parameters
+    Scene_interface::Bbox bbox = c3t3_item->bbox();
+    ui.objectName->setText(c3t3_item->name());
+
+    ui.objectNameSize->setText(
+      tr("Object bbox size (w,h,d):  <b>%1</b>,  <b>%2</b>,  <b>%3</b>")
+      .arg(bbox.xmax()-bbox.xmin(), 0, 'g', 3)
+      .arg(bbox.ymax()-bbox.ymin(), 0, 'g', 3)
+      .arg(bbox.zmax()-bbox.zmin(), 0, 'g', 3));
+
+    double diago_length = CGAL::sqrt((bbox.xmax()-bbox.xmin())*(bbox.xmax()-bbox.xmin())
+                                   + (bbox.ymax()-bbox.ymin())*(bbox.ymax()-bbox.ymin())
+                                   + (bbox.zmax()-bbox.zmin())*(bbox.zmax()-bbox.zmin()));
+    double log = std::log10(diago_length);
+    unsigned int nb_decimals = (log > 0) ? 5 : (std::ceil(-log)+3);
+
+    ui.edgeLength_dspinbox->setDecimals(nb_decimals);
+    ui.edgeLength_dspinbox->setSingleStep(1e-3);
+    ui.edgeLength_dspinbox->setRange(1e-6 * diago_length, //min
+                                     2.   * diago_length);//max
+    ui.edgeLength_dspinbox->setValue(0.05 * diago_length);
+
+    std::ostringstream oss;
+    oss << "Diagonal length of the Bbox of the triangulation to remesh is ";
+    oss << diago_length << "." << std::endl;
+    oss << "Default is 5% of it" << std::endl;
+    ui.edgeLength_dspinbox->setToolTip(QString::fromStdString(oss.str()));
+
+    ui.nbIterations_spinbox->setSingleStep(1);
+    ui.nbIterations_spinbox->setRange(1/*min*/, 1000/*max*/);
+    ui.nbIterations_spinbox->setValue(1);
+
+    ui.protect_checkbox->setChecked(false);
+
+    return ui;
+  }
+
+
+private:
+  QAction* actionTetrahedralRemeshing_;
+
+}; // end Polyhedron_demo_tetrahedral_remeshing_plugin
+
+#include "Tetrahedral_remeshing_plugin.moc"
diff --git a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
index 01c192db153..9e8beb2e5a7 100644
--- a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.cpp
@@ -157,7 +157,7 @@ public :
     const EPICK::Plane_3& plane = qobject_cast<Scene_c3t3_item*>(this->parent())->plane();
     float shrink_factor = qobject_cast<Scene_c3t3_item*>(this->parent())->getShrinkFactor();
     QVector4D cp = cgal_plane_to_vector4d(plane);
-    getTriangleContainer(0)->setPlane(cp);
+    getTriangleContainer(0)->setPlane(-cp);
     getTriangleContainer(0)->setShrinkFactor(shrink_factor);
     // positions_poly is also used for the faces in the cut plane
     // and changes when the cut plane is moved
@@ -569,8 +569,10 @@ Scene_c3t3_item::Scene_c3t3_item(const C3t3& c3t3, bool is_surface)
   : Scene_group_item("unnamed")
   , d(new Scene_c3t3_item_priv(c3t3, this))
 {
-  d->reset_cut_plane();
   common_constructor(is_surface);
+  d->reset_cut_plane();
+  c3t3_changed();
+  changed();
 }
 
 Scene_c3t3_item::~Scene_c3t3_item()
@@ -1428,6 +1430,7 @@ void Scene_c3t3_item_priv::computeElements()
 
   //The grid
   {
+    positions_grid.resize(0);
 
     float x = (2 * (float)complex_diag()) / 10.0f;
     float y = (2 * (float)complex_diag()) / 10.0f;
@@ -2097,5 +2100,11 @@ void Scene_c3t3_item::newViewer(Viewer_interface *viewer)
     d->computeIntersections(viewer);
   }
 }
+
+Scene_c3t3_item* Scene_c3t3_item::clone() const
+{
+  return new Scene_c3t3_item(d->c3t3, d->is_surface);
+}
+
 #include "Scene_c3t3_item.moc"
 
diff --git a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h
index 1c2e4316451..90b02e87c7b 100644
--- a/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h
+++ b/Polyhedron/demo/Polyhedron/Scene_c3t3_item.h
@@ -101,9 +101,8 @@ public:
   {
       return Scene_item::bbox();
   }
-  Scene_c3t3_item* clone() const  Q_DECL_OVERRIDE{
-    return 0;
-  }
+
+  Scene_c3t3_item* clone() const  Q_DECL_OVERRIDE;
 
   bool load_binary(std::istream& is);
 
diff --git a/Polyhedron/demo/Polyhedron/Scene_polygon_soup_item.cpp b/Polyhedron/demo/Polyhedron/Scene_polygon_soup_item.cpp
index ea3d533d38b..ff00b053aac 100644
--- a/Polyhedron/demo/Polyhedron/Scene_polygon_soup_item.cpp
+++ b/Polyhedron/demo/Polyhedron/Scene_polygon_soup_item.cpp
@@ -514,7 +514,7 @@ Scene_polygon_soup_item::toolTip() const
     return QString();
 
   QString str = QObject::tr("<p><b>%1</b> (mode: %5, color: %6)<br />"
-                     "<i>Polygons soup</i></p>"
+                     "<i>Polygon soup</i></p>"
                      "<p>Number of vertices: %2<br />"
                      "Number of polygons: %3</p>")
     .arg(this->name())
diff --git a/Polyhedron/demo/Polyhedron/Server_ws.cpp b/Polyhedron/demo/Polyhedron/Server_ws.cpp
new file mode 100644
index 00000000000..82bea309a37
--- /dev/null
+++ b/Polyhedron/demo/Polyhedron/Server_ws.cpp
@@ -0,0 +1,100 @@
+#include <QtCore/QCoreApplication>
+#include <QtCore/QCommandLineParser>
+#include <QtCore/QCommandLineOption>
+#include <QNetworkInterface>
+#include <QApplication>
+#include <QMessageBox>
+#include "Server_ws.h"
+
+#include <iostream>
+
+
+EchoServer::EchoServer(quint16 port) :
+  QObject(),
+  m_pWebSocketServer(new QWebSocketServer(QStringLiteral("Echo Server"),
+                                          QWebSocketServer::NonSecureMode, this))
+{
+  if (m_pWebSocketServer->listen(QHostAddress::Any, port)) {
+    connect(m_pWebSocketServer, &QWebSocketServer::newConnection,
+            this, &EchoServer::onNewConnection);
+    connect(m_pWebSocketServer, &QWebSocketServer::closed, this, &EchoServer::closed);
+  }
+  QHostAddress local_host("0.0.0.0");
+
+  //to avoid printing 127.0.0.1. Not realy sure it won't ever print the external ipv4 though.
+  const QHostAddress &localhost = QHostAddress(QHostAddress::LocalHost);
+  for (const QHostAddress &address: QNetworkInterface::allAddresses()) {
+    if (address.protocol() == QAbstractSocket::IPv4Protocol && address != localhost)
+    {
+      local_host= address;
+      break;
+    }
+  }
+  QMessageBox mb(QMessageBox::NoIcon, "WS Server",
+                 tr("WebSockets Server started.\nEnter the following address in\nyour Network Preferences to be able to join it :\n"
+                    "ws://%1:%2").arg(local_host.toString()).arg(port), QMessageBox::Ok);
+  mb.setTextInteractionFlags(Qt::TextSelectableByMouse);
+  mb.exec();
+}
+
+EchoServer::~EchoServer()
+{
+  m_pWebSocketServer->close();
+  qDeleteAll(m_clients.begin(), m_clients.end());
+}
+
+void EchoServer::onNewConnection()
+{
+  QWebSocket *pSocket = m_pWebSocketServer->nextPendingConnection();
+
+  connect(pSocket, &QWebSocket::textMessageReceived, this, &EchoServer::processTextMessage);
+  connect(pSocket, &QWebSocket::binaryMessageReceived, this, &EchoServer::processBinaryMessage);
+  connect(pSocket, &QWebSocket::disconnected, this, &EchoServer::socketDisconnected);
+
+  m_clients << pSocket;
+}
+
+void EchoServer::processTextMessage(QString message)
+{
+  QWebSocket *pClient = qobject_cast<QWebSocket *>(sender());
+  for(auto *client : m_clients) {
+    if(client != pClient)
+      client->sendTextMessage(message);
+  }
+}
+
+void EchoServer::processBinaryMessage(QByteArray message)
+{
+  QWebSocket *pClient = qobject_cast<QWebSocket *>(sender());
+  if (pClient) {
+    pClient->sendBinaryMessage(message);
+  }
+}
+
+void EchoServer::socketDisconnected()
+{
+  QWebSocket *pClient = qobject_cast<QWebSocket *>(sender());
+  if (pClient) {
+    m_clients.removeAll(pClient);
+    pClient->deleteLater();
+  }
+}
+
+int main(int argc, char *argv[])
+{
+  QApplication a(argc, argv);
+  QCommandLineParser parser;
+  parser.setApplicationDescription("WS Server");
+  parser.addHelpOption();
+  QCommandLineOption portOption(QStringList() << "p" << "port",
+                                QCoreApplication::translate("main", "Port for echoserver [default: 1234]."),
+                                QCoreApplication::translate("main", "port"), QLatin1Literal("1234"));
+  parser.addOption(portOption);
+  parser.process(a);
+  int port = parser.value(portOption).toInt();
+  EchoServer *server = new EchoServer(port);
+  QObject::connect(server, &EchoServer::closed, &a, &QCoreApplication::quit);
+
+  return a.exec();
+}
+
diff --git a/Polyhedron/demo/Polyhedron/Server_ws.h b/Polyhedron/demo/Polyhedron/Server_ws.h
new file mode 100644
index 00000000000..fe94f6b2d08
--- /dev/null
+++ b/Polyhedron/demo/Polyhedron/Server_ws.h
@@ -0,0 +1,30 @@
+#ifndef SERVER_WS_H
+#define SERVER_WS_H
+
+#include  <QObject>
+#include <QWebSocketServer>
+#include <QWebSocket>
+
+class EchoServer : public QObject
+{
+  Q_OBJECT
+public:
+  explicit EchoServer(quint16 port);
+  ~EchoServer();
+
+
+Q_SIGNALS:
+  void closed();
+
+private Q_SLOTS:
+  void onNewConnection();
+  void processTextMessage(QString message);
+  void processBinaryMessage(QByteArray message);
+  void socketDisconnected();
+
+private:
+  QWebSocketServer *m_pWebSocketServer;
+  QList<QWebSocket *> m_clients;
+};
+
+#endif // SERVER_WS_H
diff --git a/Polyhedron/demo/Polyhedron/Use_ssh.cpp b/Polyhedron/demo/Polyhedron/Use_ssh.cpp
index 8acc1801b8e..028909251c2 100644
--- a/Polyhedron/demo/Polyhedron/Use_ssh.cpp
+++ b/Polyhedron/demo/Polyhedron/Use_ssh.cpp
@@ -20,8 +20,10 @@
 #include <vector>
 #include <chrono>
 #include <thread>
+#include <sstream>
 
 #include <QMessageBox>
+#include <QStringList>
 
 bool test_result(int res)
 {
@@ -135,6 +137,79 @@ bool establish_ssh_session(ssh_session &session,
   return true;
 }
 
+
+bool establish_ssh_session_from_agent(ssh_session& session,
+                                      const char *user,
+                                      const char *server,
+                                      const char *pub_key_path)
+{
+  int port = 22;
+
+  //Can use SSH_LOG_PROTOCOL here for verbose output
+  int verbosity = SSH_LOG_NOLOG;
+  int res;
+  //retry 4 times max each time the connection asks to be retried.
+  for(int k = 0; k < 4; ++k)
+  {
+    session = ssh_new();
+    ssh_options_set( session, SSH_OPTIONS_LOG_VERBOSITY, &verbosity );
+    ssh_options_set( session, SSH_OPTIONS_PORT, &port );
+    ssh_options_set( session, SSH_OPTIONS_USER, user );
+    ssh_options_set( session, SSH_OPTIONS_HOST, server);
+
+    ssh_connect(session);
+#if LIBSSH_VERSION_MAJOR <1 && LIBSSH_VERSION_MINOR < 8
+    if( ssh_is_server_known(session) != SSH_SERVER_KNOWN_OK )
+#else
+      if( ssh_session_is_known_server(session) != SSH_KNOWN_HOSTS_OK )
+#endif
+    {
+      if(QMessageBox::warning(CGAL::Three::Three::mainWindow(), QString("Unknown Server"),
+                              QString ("The server you are trying to join is not known.\n"
+                                       "Do you wish to add it to the known servers list and continue?"),
+                              QMessageBox::Yes | QMessageBox::No) != QMessageBox::Yes)
+      {
+        return false;
+      }
+#if LIBSSH_VERSION_MAJOR <1 && LIBSSH_VERSION_MINOR < 8
+      if( ssh_write_knownhost(session) != SSH_OK )
+#else
+      if( ssh_session_update_known_hosts(session) != SSH_OK )
+#endif
+      {
+        std::cerr << "writeKnownHost failed" << std::endl;
+        return false;
+      }
+      else
+      {
+        ssh_connect(session);
+      }
+    }
+      ssh_key pubkey = ssh_key_new();
+      ssh_pki_import_pubkey_file(pub_key_path, &pubkey);
+      res = ssh_userauth_try_publickey(session, NULL, pubkey);
+      if(res == SSH_AUTH_AGAIN)
+        ssh_disconnect(session);
+      else
+        break;
+    }
+
+
+  if(!test_result(res))
+  {
+    ssh_disconnect(session);
+    return false;
+  }
+
+  res = ssh_userauth_agent(session, user);
+  if(!test_result(res))
+  {
+    ssh_disconnect(session);
+    return false;
+  }
+  return true;
+}
+
 void close_connection(ssh_session &session)
 {
   ssh_disconnect(session);
@@ -282,5 +357,62 @@ bool pull_file(ssh_session &session,
   return true;
 }
 
-}}
+bool explore_the_galaxy(ssh_session &session,
+                        QStringList& files)
+{
+  ssh_channel channel;
+  int rc;
+  channel = ssh_channel_new(session);
+  if (channel == NULL) return false;
+  rc = ssh_channel_open_session(channel);
+  if (rc != SSH_OK)
+  {
+    ssh_channel_free(channel);
+    return rc;
+  }
+  rc = ssh_channel_request_exec(channel, "ls /tmp");
+  if (rc != SSH_OK)
+  {
+    ssh_channel_close(channel);
+    ssh_channel_free(channel);
+    return rc;
+  }
+
+  char buffer[256];
+  int nbytes;
+  nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
+  while (nbytes > 0)
+  {
+
+    std::string sbuf(buffer, nbytes);
+    if(sbuf.find("Polyhedron_demo_") != std::string::npos)
+    {
+      std::istringstream iss(sbuf);
+      std::string file;
+      while(iss >> file)
+      {
+        if(file.find("Polyhedron_demo_") != std::string::npos)
+        {
+          QString name(file.c_str());
+          files.push_back(name.remove("Polyhedron_demo_"));
+        }
+      }
+    }
+
+    nbytes = ssh_channel_read(channel, buffer, sizeof(buffer), 0);
+  }
+  if (nbytes < 0)
+  {
+    ssh_channel_close(channel);
+    ssh_channel_free(channel);
+    return false;
+  }
+  ssh_channel_send_eof(channel);
+  ssh_channel_close(channel);
+  ssh_channel_free(channel);
+  return true;
+}
+
+}// end of ssh_internal
+}// end of CGAL
 #endif
diff --git a/Polyhedron/demo/Polyhedron/Viewer.cpp b/Polyhedron/demo/Polyhedron/Viewer.cpp
index ecadeba815a..57ed3f9d84f 100644
--- a/Polyhedron/demo/Polyhedron/Viewer.cpp
+++ b/Polyhedron/demo/Polyhedron/Viewer.cpp
@@ -1690,6 +1690,12 @@ void Viewer::setTotalPass(int p)
 
 void Viewer::messageLogged(QOpenGLDebugMessage msg)
 {
+  //filter out useless warning
+  // From those two links, we decided we didn't care for this warning:
+  // https://community.khronos.org/t/vertex-shader-in-program-2-is-being-recompiled-based-on-gl-state/76019
+  // https://stackoverflow.com/questions/12004396/opengl-debug-context-performance-warning
+  if(msg.message().contains("is being recompiled"))
+    return;
   QString error;
 
   // Format based on severity
@@ -2017,7 +2023,15 @@ void Viewer::onTextMessageSocketReceived(QString message)
   if(session != d->session){
     return;
   }
-  moveCameraToCoordinates(position, 0.05f);
+  QStringList sl = position.split(" ");
+  if(sl.size() != 7)
+    return;
+
+  CGAL::qglviewer::Vec pos(sl[0].toDouble(),sl[1].toDouble(),sl[2].toDouble());
+  CGAL::qglviewer::Quaternion q(sl[3].toDouble(),sl[4].toDouble(),
+      sl[5].toDouble(),sl[6].toDouble());
+  camera()->frame()->setPositionAndOrientation(pos, q);
+  update();
 }
 #endif
 #include "Viewer.moc"
diff --git a/Polyhedron/demo/Polyhedron/include/CGAL/Use_ssh.h b/Polyhedron/demo/Polyhedron/include/CGAL/Use_ssh.h
index 2cdca27452b..5d24a129302 100644
--- a/Polyhedron/demo/Polyhedron/include/CGAL/Use_ssh.h
+++ b/Polyhedron/demo/Polyhedron/include/CGAL/Use_ssh.h
@@ -1,6 +1,10 @@
 #ifndef USE_SSH_H
 #define USE_SSH_H
 #include <libssh/libsshpp.hpp>
+#include <vector>
+
+class QStringList;
+
 namespace CGAL{
 namespace ssh_internal{
 //should be used inside a try/catch(ssh::SshException e)
@@ -12,6 +16,12 @@ bool establish_ssh_session(ssh_session& session,
                            const char *pub_key_path,
                            const char *priv_key_path,
                            const char *priv_key_password);
+
+bool establish_ssh_session_from_agent(ssh_session& session,
+                                      const char *user,
+                                      const char *server,
+                                      const char *pub_key_path);
+
 void close_connection(ssh_session& session);
 
 bool push_file(ssh_session& session,
@@ -21,5 +31,8 @@ bool pull_file(ssh_session &session,
                const char *from_path,
                const char *to_path);
 
+bool explore_the_galaxy(ssh_session &session,
+                        QStringList &files);
+
 }}
 #endif
diff --git a/Polynomial/include/CGAL/Polynomial/Polynomial_type.h b/Polynomial/include/CGAL/Polynomial/Polynomial_type.h
index b30cf524458..540f17bd203 100644
--- a/Polynomial/include/CGAL/Polynomial/Polynomial_type.h
+++ b/Polynomial/include/CGAL/Polynomial/Polynomial_type.h
@@ -957,6 +957,52 @@ public:
     }
 
     friend Polynomial<NT> operator - <> (const Polynomial<NT>&);
+
+    //
+    // Comparison Operators
+    //
+
+    // polynomials only
+    friend bool operator == (const Polynomial& p1, const Polynomial& p2) {
+      CGAL_precondition(p1.degree() >= 0);
+      CGAL_precondition(p2.degree() >= 0);
+      if (p1.is_identical(p2)) return true;
+      if (p1.degree() != p2.degree()) return false;
+      for (int i = p1.degree(); i >= 0; i--) if (p1[i] != p2[i]) return false;
+      return true;
+    }
+    friend bool operator < (const Polynomial& p1, const Polynomial& p2)
+    { return ( p1.compare(p2) < 0 ); }
+
+    // operators NT
+    friend bool operator == (const Polynomial& p, const NT& num)  {
+      CGAL_precondition(p.degree() >= 0);
+      return p.degree() == 0 && p[0] == num;
+    }
+    friend bool operator < (const Polynomial& p,const NT& num)
+    { return ( p.compare(num) < 0 );}
+    friend bool operator > (const Polynomial& p,const NT& num)
+    { return ( p.compare(num) > 0 );}
+
+    // compare int #################################
+    friend bool operator == (const Polynomial& p, const CGAL_int(NT)& num)  {
+      CGAL_precondition(p.degree() >= 0);
+      return p.degree() == 0 && p[0] == NT(num);
+    }
+    friend bool operator < (const Polynomial& p, const CGAL_int(NT)& num)
+    { return ( p.compare(NT(num)) < 0 );}
+    friend bool operator > (const Polynomial& p, const CGAL_int(NT)& num)
+    { return ( p.compare(NT(num)) > 0 );}
+
+    // compare icoeff ###################################
+    friend bool operator == (const Polynomial& p, const CGAL_icoeff(NT)& num)  {
+      CGAL_precondition(p.degree() >= 0);
+      return p.degree() == 0 && p[0] == NT(num);
+    }
+    friend bool operator < (const Polynomial& p, const CGAL_icoeff(NT)& num)
+    { return ( p.compare(NT(num)) < 0 );}
+    friend bool operator > (const Polynomial& p, const CGAL_icoeff(NT)& num)
+    { return ( p.compare(NT(num)) > 0 );}
 }; // class Polynomial<NT_>
 
 // Arithmetic Operators, Part III:
@@ -999,102 +1045,6 @@ Polynomial<NT> operator * (const Polynomial<NT>& p1,
 }
 
 
-//
-// Comparison Operators
-//
-
-// polynomials only
-template <class NT> inline
-bool operator == (const Polynomial<NT>& p1, const Polynomial<NT>& p2) {
-  CGAL_precondition(p1.degree() >= 0);
-  CGAL_precondition(p2.degree() >= 0);
-  if (p1.is_identical(p2)) return true;
-  if (p1.degree() != p2.degree()) return false;
-  for (int i = p1.degree(); i >= 0; i--) if (p1[i] != p2[i]) return false;
-  return true;
-}
-template <class NT> inline
-bool operator < (const Polynomial<NT>& p1, const Polynomial<NT>& p2)
-{ return ( p1.compare(p2) < 0 ); }
-template <class NT> inline
-bool operator > (const Polynomial<NT>& p1, const Polynomial<NT>& p2)
-{ return ( p1.compare(p2) > 0 ); }
-
-// operators NT
-template <class NT> inline
-bool operator == (const NT& num, const Polynomial<NT>& p) {
-  CGAL_precondition(p.degree() >= 0);
-  return p.degree() == 0 && p[0] == num;
-}
-template <class NT> inline
-bool operator == (const Polynomial<NT>& p, const NT& num)  {
-  CGAL_precondition(p.degree() >= 0);
-  return p.degree() == 0 && p[0] == num;
-}
-template <class NT> inline
-bool operator < (const NT& num, const Polynomial<NT>& p)
-{ return ( p.compare(num) > 0 );}
-template <class NT> inline
-bool operator < (const Polynomial<NT>& p,const NT& num)
-{ return ( p.compare(num) < 0 );}
-template <class NT> inline
-bool operator > (const NT& num, const Polynomial<NT>& p)
-{ return ( p.compare(num) < 0 );}
-template <class NT> inline
-bool operator > (const Polynomial<NT>& p,const NT& num)
-{ return ( p.compare(num) > 0 );}
-
-
-// compare int #################################
-template <class NT> inline
-bool operator == (const CGAL_int(NT)& num, const Polynomial<NT>& p)  {
-  CGAL_precondition(p.degree() >= 0);
-  return p.degree() == 0 && p[0] == NT(num);
-}
-template <class NT> inline
-bool operator == (const Polynomial<NT>& p, const CGAL_int(NT)& num)  {
-  CGAL_precondition(p.degree() >= 0);
-  return p.degree() == 0 && p[0] == NT(num);
-}
-template <class NT> inline
-bool operator < (const CGAL_int(NT)& num, const Polynomial<NT>& p)
-{ return ( p.compare(NT(num)) > 0 );}
-template <class NT> inline
-bool operator < (const Polynomial<NT>& p, const CGAL_int(NT)& num)
-{ return ( p.compare(NT(num)) < 0 );}
-template <class NT> inline
-bool operator > (const CGAL_int(NT)& num, const Polynomial<NT>& p)
-{ return ( p.compare(NT(num)) < 0 );}
-template <class NT> inline
-bool operator > (const Polynomial<NT>& p, const CGAL_int(NT)& num)
-{ return ( p.compare(NT(num)) > 0 );}
-
-// compare icoeff ###################################
-template <class NT> inline
-bool operator == (const CGAL_icoeff(NT)& num, const Polynomial<NT>& p)  {
-  CGAL_precondition(p.degree() >= 0);
-  return p.degree() == 0 && p[0] == NT(num);
-}
-template <class NT> inline
-bool operator == (const Polynomial<NT>& p, const CGAL_icoeff(NT)& num)  {
-  CGAL_precondition(p.degree() >= 0);
-  return p.degree() == 0 && p[0] == NT(num);
-}
-template <class NT> inline
-bool operator < (const CGAL_icoeff(NT)& num, const Polynomial<NT>& p)
-{ return ( p.compare(NT(num)) > 0 );}
-template <class NT> inline
-bool operator < (const Polynomial<NT>& p, const CGAL_icoeff(NT)& num)
-{ return ( p.compare(NT(num)) < 0 );}
-
-
-template <class NT> inline
-bool operator > (const CGAL_icoeff(NT)& num, const Polynomial<NT>& p)
-{ return ( p.compare(NT(num)) < 0 );}
-template <class NT> inline
-bool operator > (const Polynomial<NT>& p, const CGAL_icoeff(NT)& num)
-{ return ( p.compare(NT(num)) > 0 );}
-
 //
 // Algebraically non-trivial operations
 //
diff --git a/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt b/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt
index d8e2d1c3387..fa25ad50bf6 100644
--- a/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt
+++ b/Principal_component_analysis/demo/Principal_component_analysis/CMakeLists.txt
@@ -19,7 +19,8 @@ include_directories( ./ )
 find_package(CGAL COMPONENTS Qt5)
 
 find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "NOTICE: This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -45,10 +46,9 @@ if(CGAL_Qt5_FOUND AND Qt5_FOUND )
   add_file_dependencies( PCA_demo.cpp "${CMAKE_CURRENT_BINARY_DIR}/MainWindow_moc.cpp"
     "${CMAKE_CURRENT_BINARY_DIR}/Viewer_moc.cpp" )
   add_executable  ( PCA_demo PCA_demo.cpp ${UI_FILES} ${CGAL_Qt5_RESOURCE_FILES} ${CGAL_Qt5_MOC_FILES})
-  CGAL_target_use_Eigen(PCA_demo)
 
   target_link_libraries( PCA_demo PRIVATE
-    CGAL::CGAL CGAL::CGAL_Qt5 Qt5::Gui)
+    CGAL::CGAL CGAL::CGAL_Qt5 CGAL::Eigen_support Qt5::Gui)
 
   add_to_cached_list( CGAL_EXECUTABLE_TARGETS PCA_demo )
 
diff --git a/Principal_component_analysis/examples/Principal_component_analysis/CMakeLists.txt b/Principal_component_analysis/examples/Principal_component_analysis/CMakeLists.txt
index acdc5826865..c5955afe2b4 100644
--- a/Principal_component_analysis/examples/Principal_component_analysis/CMakeLists.txt
+++ b/Principal_component_analysis/examples/Principal_component_analysis/CMakeLists.txt
@@ -12,14 +12,15 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
   # create a target per cppfile
   file(GLOB cppfiles RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/*.cpp)
   foreach(cppfile ${cppfiles})
     create_single_source_cgal_program( "${cppfile}" )
-    if (EIGEN3_FOUND)
+    if (TARGET CGAL::Eigen_support)
       get_filename_component(target ${cppfile} NAME_WE)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endif()
   endforeach()
 
@@ -28,4 +29,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Principal_component_analysis/test/Principal_component_analysis/CMakeLists.txt b/Principal_component_analysis/test/Principal_component_analysis/CMakeLists.txt
index 02d5f28a0ac..236ac02b1be 100644
--- a/Principal_component_analysis/test/Principal_component_analysis/CMakeLists.txt
+++ b/Principal_component_analysis/test/Principal_component_analysis/CMakeLists.txt
@@ -12,14 +12,15 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
   # create a target per cppfile
   file(GLOB cppfiles RELATIVE ${CMAKE_CURRENT_SOURCE_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/*.cpp)
   foreach(cppfile ${cppfiles})
     create_single_source_cgal_program( "${cppfile}" )
-    if (EIGEN3_FOUND)
+    if (TARGET CGAL::Eigen_support)
       get_filename_component(target ${cppfile} NAME_WE)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endif()
   endforeach()
 
@@ -28,4 +29,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Property_map/examples/Property_map/CMakeLists.txt b/Property_map/examples/Property_map/CMakeLists.txt
index d5717d3f5d2..5d251def5cf 100644
--- a/Property_map/examples/Property_map/CMakeLists.txt
+++ b/Property_map/examples/Property_map/CMakeLists.txt
@@ -33,9 +33,8 @@ endif()
 create_single_source_cgal_program( "dynamic_properties.cpp" )
 
 find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-if (EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (TARGET CGAL::Eigen_support)
   create_single_source_cgal_program( "custom_property_map.cpp" )
-  CGAL_target_use_Eigen(custom_property_map)
+  target_link_libraries(custom_property_map PUBLIC CGAL::Eigen_support)
 endif()
-
-
diff --git a/Ridges_3/examples/Ridges_3/CMakeLists.txt b/Ridges_3/examples/Ridges_3/CMakeLists.txt
index 9392ccb1b48..3fe086671df 100644
--- a/Ridges_3/examples/Ridges_3/CMakeLists.txt
+++ b/Ridges_3/examples/Ridges_3/CMakeLists.txt
@@ -10,7 +10,8 @@ if ( CGAL_FOUND )
 
   # use either Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
 
     # Link with Boost.ProgramOptions (optional)
     find_package(Boost QUIET COMPONENTS program_options)
@@ -28,11 +29,11 @@ if ( CGAL_FOUND )
    endif()
 
    create_single_source_cgal_program( Compute_Ridges_Umbilics.cpp)
-   CGAL_target_use_Eigen(Compute_Ridges_Umbilics)
+   target_link_libraries(Compute_Ridges_Umbilics PUBLIC CGAL::Eigen_support)
    create_single_source_cgal_program( Ridges_Umbilics_SM.cpp)
-   CGAL_target_use_Eigen(Ridges_Umbilics_SM)
+   target_link_libraries(Ridges_Umbilics_SM PUBLIC CGAL::Eigen_support)
    create_single_source_cgal_program( Ridges_Umbilics_LCC.cpp)
-   CGAL_target_use_Eigen(Ridges_Umbilics_LCC)
+   target_link_libraries(Ridges_Umbilics_LCC PUBLIC CGAL::Eigen_support)
 
   else()
 
diff --git a/Ridges_3/test/Ridges_3/CMakeLists.txt b/Ridges_3/test/Ridges_3/CMakeLists.txt
index 139ca8dfb10..95025861c1c 100644
--- a/Ridges_3/test/Ridges_3/CMakeLists.txt
+++ b/Ridges_3/test/Ridges_3/CMakeLists.txt
@@ -13,9 +13,10 @@ if ( CGAL_FOUND )
 
   # use either Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "ridge_test.cpp" )
-    CGAL_target_use_Eigen(ridge_test)
+    target_link_libraries(ridge_test PUBLIC CGAL::Eigen_support)
   else()
 
     message(STATUS "NOTICE: This program requires Eigen 3.1 (or greater) and will not be compiled.")
@@ -27,4 +28,3 @@ else()
   message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/STL_Extension/benchmark/compact_container_benchmark/CMakeLists.txt b/STL_Extension/benchmark/compact_container_benchmark/CMakeLists.txt
index 4bfa4327eb0..de657c74d8f 100644
--- a/STL_Extension/benchmark/compact_container_benchmark/CMakeLists.txt
+++ b/STL_Extension/benchmark/compact_container_benchmark/CMakeLists.txt
@@ -6,9 +6,10 @@ find_package(CGAL QUIET)
 
 if ( CGAL_FOUND )
   find_package( TBB )
+  include(CGAL_TBB_support)
   create_single_source_cgal_program( "cc_benchmark.cpp" )
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(cc_benchmark)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(cc_benchmark PUBLIC CGAL::TBB_support)
   endif()
 else()
   message(STATUS "This program requires the CGAL library, and will not be compiled.")
diff --git a/STL_Extension/benchmark/compact_container_benchmark/cc_benchmark.cpp b/STL_Extension/benchmark/compact_container_benchmark/cc_benchmark.cpp
index 8fa4ac28fd7..4186c723d3e 100644
--- a/STL_Extension/benchmark/compact_container_benchmark/cc_benchmark.cpp
+++ b/STL_Extension/benchmark/compact_container_benchmark/cc_benchmark.cpp
@@ -26,7 +26,7 @@ struct Truc
 {
   Truc(int v = 0) : value(v), /*value2(v), */p(NULL) {}
   void *   for_compact_container() const { return p; }
-  void * & for_compact_container()       { return p; }
+  void for_compact_container(void *ptr) { p = ptr; }
 
   int value;
   int value2;
diff --git a/STL_Extension/doc/STL_Extension/CGAL/Compact_container.h b/STL_Extension/doc/STL_Extension/CGAL/Compact_container.h
index 41c30aea6c7..98a1af5ceb6 100644
--- a/STL_Extension/doc/STL_Extension/CGAL/Compact_container.h
+++ b/STL_Extension/doc/STL_Extension/CGAL/Compact_container.h
@@ -30,10 +30,9 @@ Returns the pointer necessary for `Compact_container_traits<T>`.
 void * for_compact_container() const;
 
 /*!
-Returns a reference to the pointer necessary for
-`Compact_container_traits<T>`.
+Sets the pointer necessary for `Compact_container_traits<T>` to `p`.
 */
-void * & for_compact_container();
+void for_compact_container(void* p);
 
 /// @}
 
@@ -796,7 +795,7 @@ types `T` to make them usable with the default `Compact_container_traits`.
 
 `void * t.for_compact_container() const;`
 
-`void *& t.for_compact_container();`.
+`void t.for_compact_container(void *);`.
 
 
 */
@@ -820,11 +819,11 @@ static void * pointer(const T &t);
 /// \name Operations
 /// @{
 /*!
-Returns a reference to the pointer held by `t`.
-The template version defines this function as: `return t.for_compact_container();`
+Sets the pointer held by `t` to `p`.
+The template version defines this function as: `t.for_compact_container(p);`
 
 */
-static void * & pointer(T &t);
+  static void set_pointer(T &t, void* p);
 
 
 
diff --git a/STL_Extension/doc/STL_Extension/CGAL/Concurrent_compact_container.h b/STL_Extension/doc/STL_Extension/CGAL/Concurrent_compact_container.h
index 49d8826ba9c..65e853f489a 100644
--- a/STL_Extension/doc/STL_Extension/CGAL/Concurrent_compact_container.h
+++ b/STL_Extension/doc/STL_Extension/CGAL/Concurrent_compact_container.h
@@ -22,7 +22,7 @@ types `T` to make them usable with the default `Concurrent_compact_container`.
 
 `T` is any type providing the following member functions:
 `void * t.for_compact_container() const;`
-`void *& t.for_compact_container();`.
+`void t.for_compact_container(void *);`.
 */
 template< typename T >
 struct Concurrent_compact_container_traits {
@@ -40,11 +40,11 @@ struct Concurrent_compact_container_traits {
 /// \name Operations
 /// @{
   /*!
-  Returns a reference to the pointer held by `t`.
-  The template version defines this function as: `return t.for_compact_container();`
+  Sets the pointer held by `t` to `p`.
+  The template version defines this function as: `t.for_compact_container(p);`
 
   */
-  static void * & pointer(T &t);
+  static void set_pointer(T &t, void* p);
 
 /// @}
 
diff --git a/STL_Extension/include/CGAL/Compact_container.h b/STL_Extension/include/CGAL/Compact_container.h
index be18676e5d2..62751003b5a 100644
--- a/STL_Extension/include/CGAL/Compact_container.h
+++ b/STL_Extension/include/CGAL/Compact_container.h
@@ -25,6 +25,7 @@
 #include <vector>
 #include <cstring>
 #include <functional>
+#include <atomic>
 
 #include <CGAL/memory.h>
 #include <CGAL/iterator.h>
@@ -148,15 +149,15 @@ public:
   Compact_container_base()
   : p(nullptr) {}
   void *   for_compact_container() const { return p; }
-  void * & for_compact_container()       { return p; }
+  void for_compact_container(void* ptr)  { p = ptr; }
 };
 
 // The traits class describes the way to access the pointer.
 // It can be specialized.
 template < class T >
 struct Compact_container_traits {
-  static void *   pointer(const T &t) { return t.for_compact_container(); }
-  static void * & pointer(T &t)       { return t.for_compact_container(); }
+  static void *   pointer(const T &t)    { return t.for_compact_container(); }
+  static void set_pointer(T &t, void* p) { t.for_compact_container(p); }
 };
 
 namespace internal {
@@ -223,7 +224,8 @@ class Compact_container
 public:
   typedef typename Default::Get< TimeStamper_,
                                  CGAL::Time_stamper_impl<T> >::type
-                                                    Time_stamper_impl;
+                                                    Time_stamper;
+  typedef Time_stamper                              Time_stamper_impl; // backward-compatibility
 
   typedef T                                         value_type;
   typedef Allocator                                 allocator_type;
@@ -250,16 +252,14 @@ public:
 
   explicit Compact_container(const Allocator &a = Allocator())
   : alloc(a)
-  , time_stamper(new Time_stamper_impl())
   {
-    init ();
+    init();
   }
 
   template < class InputIterator >
   Compact_container(InputIterator first, InputIterator last,
                     const Allocator & a = Allocator())
   : alloc(a)
-  , time_stamper(new Time_stamper_impl())
   {
     init();
     std::copy(first, last, CGAL::inserter(*this));
@@ -268,14 +268,19 @@ public:
   // The copy constructor and assignment operator preserve the iterator order
   Compact_container(const Compact_container &c)
   : alloc(c.get_allocator())
-  , time_stamper(new Time_stamper_impl())
   {
     init();
     block_size = c.block_size;
-    *time_stamper = *c.time_stamper;
+    time_stamp = c.time_stamp.load();
     std::copy(c.begin(), c.end(), CGAL::inserter(*this));
   }
 
+  Compact_container(Compact_container&& c) noexcept
+  : alloc(c.get_allocator())
+  {
+    c.swap(*this);
+  }
+
   Compact_container & operator=(const Compact_container &c)
   {
     if (&c != this) {
@@ -285,10 +290,16 @@ public:
     return *this;
   }
 
+  Compact_container & operator=(Compact_container&& c) noexcept
+  {
+    Self tmp(std::move(c));
+    tmp.swap(*this);
+    return *this;
+  }
+
   ~Compact_container()
   {
     clear();
-    delete time_stamper;
   }
 
   bool is_used(const_iterator ptr) const
@@ -328,17 +339,8 @@ public:
     return all_items[block_number].first[index_in_block];
   }
 
-  void swap(Self &c)
-  {
-    std::swap(alloc, c.alloc);
-    std::swap(capacity_, c.capacity_);
-    std::swap(size_, c.size_);
-    std::swap(block_size, c.block_size);
-    std::swap(first_item, c.first_item);
-    std::swap(last_item, c.last_item);
-    std::swap(free_list, c.free_list);
-    all_items.swap(c.all_items);
-    std::swap(time_stamper, c.time_stamper);
+  friend void swap(Compact_container& a, Compact_container b) {
+    a.swap(b);
   }
 
   iterator begin() { return iterator(first_item, 0, 0); }
@@ -383,7 +385,7 @@ public:
     new (ret) value_type(args...);
     CGAL_assertion(type(ret) == USED);
     ++size_;
-    time_stamper->set_time_stamp(ret);
+    Time_stamper::set_time_stamp(ret, time_stamp);
     return iterator(ret, 0);
   }
 
@@ -397,7 +399,7 @@ public:
     std::allocator_traits<allocator_type>::construct(alloc, ret, t);
     CGAL_assertion(type(ret) == USED);
     ++size_;
-    time_stamper->set_time_stamp(ret);
+    Time_stamper::set_time_stamp(ret, time_stamp);
     return iterator(ret, 0);
   }
 
@@ -643,8 +645,8 @@ private:
     // This out of range compare is always true and causes lots of
     // unnecessary warnings.
     // CGAL_precondition(0 <= t && t < 4);
-    Traits::pointer(*ptr) = reinterpret_cast<void *>
-      (reinterpret_cast<std::ptrdiff_t>(clean_pointer((char *) p)) + (int) t);
+    Traits::set_pointer(*ptr, reinterpret_cast<void *>
+      (reinterpret_cast<std::ptrdiff_t>(clean_pointer((char *) p)) + (int) t));
   }
 
 public:
@@ -652,7 +654,21 @@ public:
   static bool is_begin_or_end(const_pointer ptr)
   { return type(ptr)==START_END; }
 
+  void swap(Self &c)
+  {
+    std::swap(alloc, c.alloc);
+    std::swap(capacity_, c.capacity_);
+    std::swap(size_, c.size_);
+    std::swap(block_size, c.block_size);
+    std::swap(first_item, c.first_item);
+    std::swap(last_item, c.last_item);
+    std::swap(free_list, c.free_list);
+    all_items.swap(c.all_items);
 
+    // non-atomic swap of time_stamp:
+    c.time_stamp = time_stamp.exchange(c.time_stamp.load());
+  }
+private:
   // We store a vector of pointers to all allocated blocks and their sizes.
   // Knowing all pointers, we don't have to walk to the end of a block to reach
   // the pointer to the next block.
@@ -660,7 +676,9 @@ public:
   // by walking through the block till its end.
   // This opens up the possibility for the compiler to optimize the clear()
   // function considerably when has_trivial_destructor<T>.
-  typedef std::vector<std::pair<pointer, size_type> >  All_items;
+  using All_items = std::vector<std::pair<pointer, size_type> >;
+
+  using time_stamp_t = std::atomic<std::size_t>;
 
   void init()
   {
@@ -671,21 +689,18 @@ public:
     first_item = nullptr;
     last_item  = nullptr;
     all_items  = All_items();
-    time_stamper->reset();
+    time_stamp = 0;
   }
 
   allocator_type   alloc;
-  size_type        capacity_;
-  size_type        size_;
-  size_type        block_size;
-  pointer          free_list;
-  pointer          first_item;
-  pointer          last_item;
-  All_items        all_items;
-
-  // This is a pointer, so that the definition of Compact_container does
-  // not require a complete type `T`.
-  Time_stamper_impl* time_stamper;
+  size_type        capacity_   = 0;
+  size_type        size_       = 0;
+  size_type        block_size  = Increment_policy::first_block_size;
+  pointer          free_list   = nullptr;
+  pointer          first_item  = nullptr;
+  pointer          last_item   = nullptr;
+  All_items        all_items   = {};
+  time_stamp_t     time_stamp  = {};
 };
 
 template < class T, class Allocator, class Increment_policy, class TimeStamper >
@@ -759,7 +774,7 @@ void Compact_container<T, Allocator, Increment_policy, TimeStamper>::allocate_ne
   for (size_type i = block_size; i >= 1; --i)
   {
     EraseCounterStrategy::set_erase_counter(*(new_block + i), 0);
-    time_stamper->initialize_time_stamp(new_block + i);
+    Time_stamper::initialize_time_stamp(new_block + i);
     put_on_free_list(new_block + i);
   }
   // We insert this new block at the end.
@@ -839,7 +854,6 @@ namespace internal {
   template < class DSC, bool Const >
   class CC_iterator
   {
-    typedef typename DSC::iterator                    iterator;
     typedef CC_iterator<DSC, Const>                   Self;
   public:
     typedef DSC                                       CC;
@@ -858,25 +872,30 @@ namespace internal {
       : ts(0)
 #endif
     {
-      m_ptr.p = nullptr;
+      m_ptr = nullptr;
     }
 
-    // Either a harmless copy-ctor,
-    // or a conversion from iterator to const_iterator.
-    CC_iterator (const iterator &it)
+    // Converting constructor from mutable to constant iterator
+    template <bool OtherConst>
+    CC_iterator(const CC_iterator<
+                typename std::enable_if<(!OtherConst && Const), DSC>::type,
+                OtherConst> &const_it)
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
-      : ts(Time_stamper_impl::time_stamp(it.operator->()))
+        : ts(Time_stamper::time_stamp(const_it.operator->()))
 #endif
     {
-      m_ptr.p = it.operator->();
+      m_ptr = const_it.operator->();
     }
 
-    // Same for assignment operator (otherwise MipsPro warns)
-    CC_iterator & operator= (const iterator &it)
+    // Assignment operator from mutable to constant iterator
+    template <bool OtherConst>
+    CC_iterator & operator= (const CC_iterator<
+                typename std::enable_if<(!OtherConst && Const), DSC>::type,
+                OtherConst> &const_it)
     {
-      m_ptr.p = it.operator->();
+      m_ptr = const_it.operator->();
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
-      ts = Time_stamper_impl::time_stamp(it.operator->());
+      ts = Time_stamper::time_stamp(const_it.operator->());
 #endif
       return *this;
     }
@@ -888,19 +907,16 @@ namespace internal {
 #endif
     {
       //CGAL_assertion (n == nullptr);
-      m_ptr.p = nullptr;
+      m_ptr = nullptr;
     }
 
   private:
 
-    typedef typename DSC::Time_stamper_impl           Time_stamper_impl;
+    typedef typename DSC::Time_stamper           Time_stamper;
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
     std::size_t ts;
 #endif
-    union {
-      pointer      p;
-      void        *vp;
-    } m_ptr;
+    pointer m_ptr;
 
     // Only Compact_container and Concurrent_compact_container should
     // access these constructors.
@@ -916,16 +932,16 @@ namespace internal {
       : ts(0)
 #endif
     {
-      m_ptr.p = ptr;
-      if (m_ptr.p == nullptr) // empty container.
+      m_ptr = ptr;
+      if (m_ptr == nullptr) // empty container.
         return;
 
-      ++(m_ptr.p); // if not empty, p = start
-      if (DSC::type(m_ptr.p) == DSC::FREE)
+      ++(m_ptr); // if not empty, p = start
+      if (DSC::type(m_ptr) == DSC::FREE)
         increment();
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
       else
-        ts = Time_stamper_impl::time_stamp(m_ptr.p);
+        ts = Time_stamper::time_stamp(m_ptr);
 #endif // CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
     }
 
@@ -935,10 +951,10 @@ namespace internal {
       : ts(0)
 #endif
     {
-      m_ptr.p = ptr;
+      m_ptr = ptr;
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
       if(ptr != nullptr){
-        ts = Time_stamper_impl::time_stamp(m_ptr.p);
+        ts = Time_stamper::time_stamp(m_ptr);
       }
 #endif // end CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
     }
@@ -947,49 +963,49 @@ namespace internal {
     void increment()
     {
       // It's either pointing to end(), or valid.
-      CGAL_assertion_msg(m_ptr.p != nullptr,
+      CGAL_assertion_msg(m_ptr != nullptr,
          "Incrementing a singular iterator or an empty container iterator ?");
-      CGAL_assertion_msg(DSC::type(m_ptr.p) != DSC::START_END,
+      CGAL_assertion_msg(DSC::type(m_ptr) != DSC::START_END,
          "Incrementing end() ?");
 
       // If it's not end(), then it's valid, we can do ++.
       do {
-        ++(m_ptr.p);
-        if (DSC::type(m_ptr.p) == DSC::USED ||
-            DSC::type(m_ptr.p) == DSC::START_END)
+        ++(m_ptr);
+        if (DSC::type(m_ptr) == DSC::USED ||
+            DSC::type(m_ptr) == DSC::START_END)
         {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
-          ts = Time_stamper_impl::time_stamp(m_ptr.p);
+          ts = Time_stamper::time_stamp(m_ptr);
 #endif
           return;
         }
-        if (DSC::type(m_ptr.p) == DSC::BLOCK_BOUNDARY)
-          m_ptr.p = DSC::clean_pointee(m_ptr.p);
+        if (DSC::type(m_ptr) == DSC::BLOCK_BOUNDARY)
+          m_ptr = DSC::clean_pointee(m_ptr);
       } while (true);
     }
 
     void decrement()
     {
       // It's either pointing to end(), or valid.
-      CGAL_assertion_msg(m_ptr.p != nullptr,
+      CGAL_assertion_msg(m_ptr != nullptr,
          "Decrementing a singular iterator or an empty container iterator ?");
-      CGAL_assertion_msg(DSC::type(m_ptr.p - 1) != DSC::START_END,
+      CGAL_assertion_msg(DSC::type(m_ptr - 1) != DSC::START_END,
          "Decrementing begin() ?");
 
       // If it's not begin(), then it's valid, we can do --.
       do {
-        --m_ptr.p;
-        if (DSC::type(m_ptr.p) == DSC::USED ||
-            DSC::type(m_ptr.p) == DSC::START_END)
+        --m_ptr;
+        if (DSC::type(m_ptr) == DSC::USED ||
+            DSC::type(m_ptr) == DSC::START_END)
         {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
-          ts = Time_stamper_impl::time_stamp(m_ptr.p);
+          ts = Time_stamper::time_stamp(m_ptr);
 #endif
           return;
         }
 
-        if (DSC::type(m_ptr.p) == DSC::BLOCK_BOUNDARY)
-          m_ptr.p = DSC::clean_pointee(m_ptr.p);
+        if (DSC::type(m_ptr) == DSC::BLOCK_BOUNDARY)
+          m_ptr = DSC::clean_pointee(m_ptr);
       } while (true);
     }
 
@@ -997,9 +1013,9 @@ namespace internal {
 
     Self & operator++()
     {
-      CGAL_assertion_msg(m_ptr.p != nullptr,
+      CGAL_assertion_msg(m_ptr != nullptr,
          "Incrementing a singular iterator or an empty container iterator ?");
-      /* CGAL_assertion_msg(DSC::type(m_ptr.p) == DSC::USED,
+      /* CGAL_assertion_msg(DSC::type(m_ptr) == DSC::USED,
          "Incrementing an invalid iterator."); */
       increment();
       return *this;
@@ -1007,10 +1023,10 @@ namespace internal {
 
     Self & operator--()
     {
-      CGAL_assertion_msg(m_ptr.p != nullptr,
+      CGAL_assertion_msg(m_ptr != nullptr,
          "Decrementing a singular iterator or an empty container iterator ?");
-      /*CGAL_assertion_msg(DSC::type(m_ptr.p) == DSC::USED
-                      || DSC::type(m_ptr.p) == DSC::START_END,
+      /*CGAL_assertion_msg(DSC::type(m_ptr) == DSC::USED
+                      || DSC::type(m_ptr) == DSC::START_END,
                       "Decrementing an invalid iterator.");*/
       decrement();
       return *this;
@@ -1022,13 +1038,13 @@ namespace internal {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
     bool is_time_stamp_valid() const
     {
-      return (ts == 0) || (ts == Time_stamper_impl::time_stamp(m_ptr.p));
+      return (ts == 0) || (ts == Time_stamper::time_stamp(m_ptr));
     }
 #endif // CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
 
-    reference operator*() const { return *(m_ptr.p); }
+    reference operator*() const { return *(m_ptr); }
 
-    pointer   operator->() const { return (m_ptr.p); }
+    pointer   operator->() const { return (m_ptr); }
 
     // For std::less...
     bool operator<(const CC_iterator& other) const
@@ -1036,7 +1052,7 @@ namespace internal {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
       assert( is_time_stamp_valid() );
 #endif
-      return Time_stamper_impl::less(m_ptr.p, other.m_ptr.p);
+      return Time_stamper::less(m_ptr, other.m_ptr);
     }
 
     bool operator>(const CC_iterator& other) const
@@ -1044,7 +1060,7 @@ namespace internal {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
       assert( is_time_stamp_valid() );
 #endif
-      return Time_stamper_impl::less(other.m_ptr.p, m_ptr.p);
+      return Time_stamper::less(other.m_ptr, m_ptr);
     }
 
     bool operator<=(const CC_iterator& other) const
@@ -1052,7 +1068,7 @@ namespace internal {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
       assert( is_time_stamp_valid() );
 #endif
-      return Time_stamper_impl::less(m_ptr.p, other.m_ptr.p)
+      return Time_stamper::less(m_ptr, other.m_ptr)
           || (*this == other);
     }
 
@@ -1061,13 +1077,13 @@ namespace internal {
 #ifdef CGAL_COMPACT_CONTAINER_DEBUG_TIME_STAMP
       assert( is_time_stamp_valid() );
 #endif
-      return Time_stamper_impl::less(other.m_ptr.p, m_ptr.p)
+      return Time_stamper::less(other.m_ptr, m_ptr)
           || (*this == other);
     }
 
     // Can itself be used for bit-squatting.
-    void *   for_compact_container() const { return (m_ptr.vp); }
-    void * & for_compact_container()       { return (m_ptr.vp); }
+    void * for_compact_container() const { return m_ptr; }
+    void for_compact_container(void* p) { m_ptr = static_cast<pointer>(p); }
   };
 
   template < class DSC, bool Const1, bool Const2 >
@@ -1119,7 +1135,7 @@ namespace handle {
   template <class H> struct Hash_functor;
 
   template<class DSC, bool Const>
-  struct Hash_functor<CC_iterator<DSC, Const>>{
+  struct Hash_functor<CC_iterator<DSC, Const> >{
     std::size_t
     operator()(const CC_iterator<DSC, Const>& i)
     {
diff --git a/STL_Extension/include/CGAL/Concurrent_compact_container.h b/STL_Extension/include/CGAL/Concurrent_compact_container.h
index 5ab9eca6790..31250293142 100644
--- a/STL_Extension/include/CGAL/Concurrent_compact_container.h
+++ b/STL_Extension/include/CGAL/Concurrent_compact_container.h
@@ -66,7 +66,7 @@ template<typename T> class has_##X {                                          \
 template < class T >
 struct Concurrent_compact_container_traits {
   static void *   pointer(const T &t) { return t.for_compact_container(); }
-  static void * & pointer(T &t)       { return t.for_compact_container(); }
+  static void set_pointer(T &t, void* p) { t.for_compact_container(p); }
 };
 
 namespace CCC_internal {
@@ -114,6 +114,8 @@ namespace CCC_internal {
 // Free list (head and size)
 template< typename pointer, typename size_type, typename CCC >
 class Free_list {
+  // Not that the implicitly-defined member functions copy the
+  // pointer, and not the pointed data.
 public:
   Free_list() : m_head(nullptr), m_size(0) {
 #if CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
@@ -150,13 +152,6 @@ public:
 #endif // CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
   }
   bool empty()               { return size() == 0; }
-  // Warning: copy the pointer, not the data!
-  Free_list& operator= (const Free_list& other)
-  {
-    m_head = other.m_head;
-    m_size = other.m_size;
-    return *this;
-  }
 
   void merge(Free_list &other)
   {
@@ -210,7 +205,8 @@ class Concurrent_compact_container
   typedef Concurrent_compact_container_traits <T>                   Traits;
 
 public:
-  typedef CGAL::Time_stamper_impl<T>                Time_stamper_impl;
+  typedef CGAL::Time_stamper_impl<T>                Time_stamper;
+  typedef Time_stamper                              Time_stamper_impl; // backward compatibility
 
   typedef T                                         value_type;
   typedef Allocator                                 allocator_type;
@@ -241,7 +237,6 @@ public:
 
   explicit Concurrent_compact_container(const Allocator &a = Allocator())
   : m_alloc(a)
-  , m_time_stamper(new Time_stamper_impl())
   {
     init ();
   }
@@ -250,7 +245,6 @@ public:
   Concurrent_compact_container(InputIterator first, InputIterator last,
                     const Allocator & a = Allocator())
   : m_alloc(a)
-  , m_time_stamper(new Time_stamper_impl())
   {
     init();
     std::copy(first, last, CGAL::inserter(*this));
@@ -259,13 +253,18 @@ public:
   // The copy constructor and assignment operator preserve the iterator order
   Concurrent_compact_container(const Concurrent_compact_container &c)
   : m_alloc(c.get_allocator())
-  , m_time_stamper(new Time_stamper_impl())
   {
     init();
     m_block_size = c.m_block_size;
     std::copy(c.begin(), c.end(), CGAL::inserter(*this));
   }
 
+  Concurrent_compact_container(Concurrent_compact_container&& c) noexcept
+  : m_alloc(c.get_allocator())
+  {
+    c.swap(*this);
+  }
+
   Concurrent_compact_container & operator=(const Concurrent_compact_container &c)
   {
     if (&c != this) {
@@ -275,10 +274,16 @@ public:
     return *this;
   }
 
+  Concurrent_compact_container & operator=(Concurrent_compact_container&& c) noexcept
+  {
+    Self tmp(std::move(c));
+    tmp.swap(*this);
+    return *this;
+  }
+
   ~Concurrent_compact_container()
   {
     clear();
-    delete m_time_stamper;
   }
 
   bool is_used(const_iterator ptr) const
@@ -290,11 +295,8 @@ public:
   {
     std::swap(m_alloc, c.m_alloc);
 #if CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
-    { // non-atomic swap
-      size_type other_capacity = c.m_capacity;
-      c.m_capacity = size_type(m_capacity);
-      m_capacity = other_capacity;
-    }
+    // non-atomic swap of m_capacity
+    c.m_capacity = m_capacity.exchange(c.m_capacity.load());
 #else // not CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
     std::swap(m_capacity, c.m_capacity);
 #endif // not CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
@@ -304,7 +306,12 @@ public:
     std::swap(m_last_item, c.m_last_item);
     std::swap(m_free_lists, c.m_free_lists);
     m_all_items.swap(c.m_all_items);
-    std::swap(m_time_stamper, c.m_time_stamper);
+    // non-atomic swap of m_time_stamp
+    c.m_time_stamp = m_time_stamp.exchange(c.m_time_stamp.load());
+  }
+
+  friend void swap(Concurrent_compact_container& a, Concurrent_compact_container& b) {
+    a.swap(b);
   }
 
   iterator begin() { return iterator(m_first_item, 0, 0); }
@@ -544,7 +551,7 @@ private:
   {
     CGAL_assertion(type(ret) == USED);
     fl->dec_size();
-    m_time_stamper->set_time_stamp(ret);
+    Time_stamper::set_time_stamp(ret, m_time_stamp);
     return iterator(ret, 0);
   }
 
@@ -606,8 +613,8 @@ private:
     // This out of range compare is always true and causes lots of
     // unnecessary warnings.
     // CGAL_precondition(0 <= t && t < 4);
-    Traits::pointer(*ptr) = reinterpret_cast<void *>
-      (reinterpret_cast<std::ptrdiff_t>(clean_pointer((char *) p)) + (int) t);
+    Traits::set_pointer(*ptr, reinterpret_cast<void *>
+      (reinterpret_cast<std::ptrdiff_t>(clean_pointer((char *) p)) + (int) t));
   }
 
   typedef tbb::queuing_mutex Mutex;
@@ -619,8 +626,9 @@ private:
   // by walking through the block till its end.
   // This opens up the possibility for the compiler to optimize the clear()
   // function considerably when has_trivial_destructor<T>.
-  typedef std::vector<std::pair<pointer, size_type> >  All_items;
+  using All_items = std::vector<std::pair<pointer, size_type> >;
 
+  using time_stamp_t = std::atomic<std::size_t>;
 
   void init()
   {
@@ -636,25 +644,23 @@ private:
     m_first_item = nullptr;
     m_last_item  = nullptr;
     m_all_items  = All_items();
-    m_time_stamper->reset();
+    m_time_stamp = 0;
   }
 
   allocator_type    m_alloc;
 #if CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
-  std::atomic<size_type> m_capacity;
+  std::atomic<size_type> m_capacity = {};
 #else // not CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
-  size_type         m_capacity;
+  size_type         m_capacity      = {};
 #endif // not CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE
-  size_type         m_block_size;
+  size_type         m_block_size    = CGAL_INIT_CONCURRENT_COMPACT_CONTAINER_BLOCK_SIZE;
   Free_lists        m_free_lists;
-  pointer           m_first_item;
-  pointer           m_last_item;
-  All_items         m_all_items;
+  pointer           m_first_item    = nullptr;
+  pointer           m_last_item     = nullptr;
+  All_items         m_all_items     = {};
   mutable Mutex     m_mutex;
+  time_stamp_t      m_time_stamp    = {};
 
-  // This is a pointer, so that the definition of Compact_container does
-  // not require a complete type `T`.
-  Time_stamper_impl* m_time_stamper;
 };
 
 template < class T, class Allocator >
@@ -718,7 +724,7 @@ void Concurrent_compact_container<T, Allocator>::clear()
     size_type s = it->second;
     for (pointer pp = p + 1; pp != p + s - 1; ++pp) {
       if (type(pp) == USED)
-        m_alloc.destroy(pp);
+        std::allocator_traits<allocator_type>::destroy(m_alloc, pp);
     }
     m_alloc.deallocate(p, s);
   }
@@ -770,7 +776,7 @@ void Concurrent_compact_container<T, Allocator>::
   for (size_type i = old_block_size; i >= 1; --i)
   {
     EraseCounterStrategy::set_erase_counter(*(new_block + i), 0);
-    m_time_stamper->initialize_time_stamp(new_block + i);
+    Time_stamper::initialize_time_stamp(new_block + i);
     put_on_free_list(new_block + i, fl);
   }
 }
diff --git a/STL_Extension/include/CGAL/Handle.h b/STL_Extension/include/CGAL/Handle.h
index ca3366524cb..0d652ccb4cb 100644
--- a/STL_Extension/include/CGAL/Handle.h
+++ b/STL_Extension/include/CGAL/Handle.h
@@ -40,31 +40,31 @@ class Handle
     typedef std::ptrdiff_t Id_type ;
 
     Handle() noexcept
-        : PTR{static_cast<Rep*>(0)} {}
+        : PTR(static_cast<Rep*>(0)) {}
 
     // FIXME: if the precondition throws in a noexcept function, the program terminates
     Handle(const Handle& x) noexcept
     {
-      CGAL_precondition( x.PTR.p != static_cast<Rep*>(0) );
-      PTR.p = x.PTR.p;
-      CGAL_assume (PTR.p->count > 0);
-      PTR.p->count++;
+      CGAL_precondition( x.PTR != static_cast<Rep*>(0) );
+      PTR = x.PTR;
+      CGAL_assume (PTR->count > 0);
+      PTR->count++;
     }
 
     ~Handle()
     {
-        if ( PTR.p && (--PTR.p->count == 0))
-            delete PTR.p;
+        if ( PTR && (--PTR->count == 0))
+            delete PTR;
     }
 
     Handle&
     operator=(const Handle& x) noexcept
     {
-      CGAL_precondition( x.PTR.p != static_cast<Rep*>(0) );
-      x.PTR.p->count++;
-      if ( PTR.p && (--PTR.p->count == 0))
-          delete PTR.p;
-      PTR.p = x.PTR.p;
+      CGAL_precondition( x.PTR != static_cast<Rep*>(0) );
+      x.PTR->count++;
+      if ( PTR && (--PTR->count == 0))
+          delete PTR;
+      PTR = x.PTR;
       return *this;
     }
 
@@ -72,29 +72,25 @@ class Handle
 
     void reset()
     {
-      if (PTR.p)
+      if (PTR)
       {
-        if (--PTR.p->count==0)
-          delete PTR.p;
-        PTR.p=0;
+        if (--PTR->count==0)
+          delete PTR;
+        PTR=0;
       }
     }
 
-    int refs()  const noexcept { return PTR.p->count; }
+    int
+    refs()  const noexcept { return PTR->count; }
 
-    Id_type id() const noexcept { return PTR.p - static_cast<Rep*>(0); }
+    Id_type id() const noexcept { return PTR - static_cast<Rep*>(0); }
 
-    bool identical(const Handle& h) const noexcept { return PTR.p == h.PTR.p; }
-
-    void*  for_compact_container() const { return PTR.vp; }
-    void*& for_compact_container() { return PTR.vp; }
+    bool identical(const Handle& h) const noexcept { return PTR == h.PTR; }
 
+    void * for_compact_container() const { return PTR; }
+    void for_compact_container(void* p) { PTR = static_cast<Rep*>(p); }
   protected:
-
-  union {
-    Rep* p;
-    void* vp;
-  } PTR;
+    Rep* PTR;
 };
 
 //inline Handle::Id_type id(const Handle& x) { return x.id() ; }
diff --git a/STL_Extension/include/CGAL/Time_stamper.h b/STL_Extension/include/CGAL/Time_stamper.h
index 6d65ec3cfb1..f0cfe44a574 100644
--- a/STL_Extension/include/CGAL/Time_stamper.h
+++ b/STL_Extension/include/CGAL/Time_stamper.h
@@ -28,26 +28,12 @@ constexpr size_t rounded_down_log2(size_t n)
 template <typename T>
 struct Time_stamper
 {
-  Time_stamper()
-   : time_stamp_() {}
-
-  Time_stamper(const Time_stamper& ts)
-    : time_stamp_()
-  {
-    time_stamp_ = std::size_t(ts.time_stamp_);
-  }
-
-  Time_stamper& operator=(const Time_stamper& ts)
-  {
-    time_stamp_ = std::size_t(ts.time_stamp_);
-    return *this;
-  }
-
   static void initialize_time_stamp(T* pt) {
     pt->set_time_stamp(std::size_t(-1));
   }
 
-  void set_time_stamp(T* pt) {
+  template <typename time_stamp_t>
+  static void set_time_stamp(T* pt, time_stamp_t& time_stamp_) {
     if(pt->time_stamp() == std::size_t(-1)) {
       const std::size_t new_ts = time_stamp_++;
       pt->set_time_stamp(new_ts);
@@ -96,23 +82,14 @@ struct Time_stamper
       return time_stamp(p_t1) < time_stamp(p_t2);
     }
   }
-
-  void reset() {
-    time_stamp_ = 0;
-  }
-private:
-#ifdef CGAL_NO_ATOMIC
-  std::size_t time_stamp_;
-#else
-  CGAL::cpp11::atomic<std::size_t> time_stamp_;
-#endif
 }; // end class template Time_stamper<T>
 
 template <typename T>
 struct No_time_stamp
 {
 public:
-  void set_time_stamp(T*)  {}
+  template <typename time_stamp_t>
+  static void set_time_stamp(T*, time_stamp_t&)  {}
   static bool less(const T* p_t1,const T* p_t2) {
     return p_t1 < p_t2;
   }
@@ -130,8 +107,6 @@ public:
     constexpr std::size_t shift = internal::rounded_down_log2(sizeof(T));
     return reinterpret_cast<std::size_t>(p) >> shift;
   }
-
-  void reset()                {}
 }; // end class template No_time_stamp<T>
 
 // That class template is an auxiliary class.  It has a
diff --git a/STL_Extension/include/CGAL/assertions.h b/STL_Extension/include/CGAL/assertions.h
index 57698d51da9..caa0237fc7d 100644
--- a/STL_Extension/include/CGAL/assertions.h
+++ b/STL_Extension/include/CGAL/assertions.h
@@ -54,9 +54,9 @@ namespace CGAL {
 // =====================
 // failure functions
 // -----------------
-CGAL_EXPORT CGAL_NORETURN void assertion_fail      ( const char*, const char*, int, const char* = "") ;
-CGAL_EXPORT CGAL_NORETURN void precondition_fail   ( const char*, const char*, int, const char* = "") ;
-CGAL_EXPORT CGAL_NORETURN void postcondition_fail  ( const char*, const char*, int, const char* = "") ;
+[[noreturn]] CGAL_EXPORT void assertion_fail      ( const char*, const char*, int, const char* = "") ;
+[[noreturn]] CGAL_EXPORT void precondition_fail   ( const char*, const char*, int, const char* = "") ;
+[[noreturn]] CGAL_EXPORT void postcondition_fail  ( const char*, const char*, int, const char* = "") ;
 
 // warning function
 // ----------------
diff --git a/STL_Extension/test/STL_Extension/CMakeLists.txt b/STL_Extension/test/STL_Extension/CMakeLists.txt
index 80563069300..4a427003e02 100644
--- a/STL_Extension/test/STL_Extension/CMakeLists.txt
+++ b/STL_Extension/test/STL_Extension/CMakeLists.txt
@@ -12,6 +12,7 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
 
   create_single_source_cgal_program( "test_Boolean_tag.cpp" )
   create_single_source_cgal_program( "test_Cache.cpp" )
@@ -21,8 +22,8 @@ if ( CGAL_FOUND )
   create_single_source_cgal_program( "test_composition.cpp" )
   create_single_source_cgal_program( "test_Concatenate_iterator.cpp" )
   create_single_source_cgal_program( "test_Concurrent_compact_container.cpp" )
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(test_Concurrent_compact_container)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(test_Concurrent_compact_container PUBLIC CGAL::TBB_support)
   endif()
   create_single_source_cgal_program( "test_dispatch_output.cpp" )
   create_single_source_cgal_program( "test_Flattening_iterator.cpp" )
@@ -43,12 +44,11 @@ if ( CGAL_FOUND )
   create_single_source_cgal_program( "test_vector.cpp" )
   create_single_source_cgal_program( "test_join_iterators.cpp" )
   create_single_source_cgal_program( "test_for_each.cpp" )
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(test_for_each)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(test_for_each PUBLIC CGAL::TBB_support)
   endif()
 else()
 
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/STL_Extension/test/STL_Extension/test_Compact_container.cpp b/STL_Extension/test/STL_Extension/test_Compact_container.cpp
index 7581805f4ed..7be7166feff 100644
--- a/STL_Extension/test/STL_Extension/test_Compact_container.cpp
+++ b/STL_Extension/test/STL_Extension/test_Compact_container.cpp
@@ -4,6 +4,7 @@
 #include <cstddef>
 #include <list>
 #include <vector>
+#include <type_traits>
 #include <CGAL/Compact_container.h>
 #include <CGAL/Random.h>
 
@@ -71,7 +72,7 @@ public:
   bool operator< (const Node_2 &n) const { return rnd <  n.rnd; }
 
   void *   for_compact_container() const { return p_cc; }
-  void * & for_compact_container()       { return p_cc; }
+  void for_compact_container(void *p)       { p_cc = p; }
 };
 
 template < class Cont >
@@ -83,6 +84,11 @@ inline bool check_empty(const Cont &c)
 template < class Cont >
 void test(const Cont &)
 {
+  static_assert(std::is_nothrow_move_constructible<Cont>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Cont>::value,
+                "move assignment is missing");
+
   // Testing if all types are provided.
 
   typename Cont::value_type              t0;
@@ -319,22 +325,22 @@ int main()
 
   // Check the time stamper policies
   if(! boost::is_base_of<CGAL::Time_stamper<T1>,
-     C1::Time_stamper_impl>::value)
+     C1::Time_stamper>::value)
   {
     std::cerr << "Error timestamper of C1\n"; return 1;
   }
   if(! boost::is_base_of<CGAL::No_time_stamp<T2>,
-     C2::Time_stamper_impl>::value)
+     C2::Time_stamper>::value)
   {
     std::cerr << "Error timestamper of C2\n"; return 1;
   }
   if(! boost::is_base_of<CGAL::No_time_stamp<T3>,
-     C3::Time_stamper_impl>::value)
+     C3::Time_stamper>::value)
   {
     std::cerr << "Error timestamper of C3\n"; return 1;
   }
   if(! boost::is_base_of<CGAL::Time_stamper<T2>,
-     C4::Time_stamper_impl>::value)
+     C4::Time_stamper>::value)
   {
     std::cerr << "Error timestamper of C4\n"; return 1;
   }
diff --git a/STL_Extension/test/STL_Extension/test_Compact_container_is_used.cpp b/STL_Extension/test/STL_Extension/test_Compact_container_is_used.cpp
index aac89dc61d5..2d810602cde 100644
--- a/STL_Extension/test/STL_Extension/test_Compact_container_is_used.cpp
+++ b/STL_Extension/test/STL_Extension/test_Compact_container_is_used.cpp
@@ -15,7 +15,7 @@ public:
   {}
 
   void *   for_compact_container() const { return p_cc; }
-  void * & for_compact_container()       { return p_cc; }
+  void for_compact_container(void *p) { p_cc = p; }
 };
 
 int main()
diff --git a/STL_Extension/test/STL_Extension/test_Concurrent_compact_container.cpp b/STL_Extension/test/STL_Extension/test_Concurrent_compact_container.cpp
index 2f4803c4fb2..d4fa4a1467a 100644
--- a/STL_Extension/test/STL_Extension/test_Concurrent_compact_container.cpp
+++ b/STL_Extension/test/STL_Extension/test_Concurrent_compact_container.cpp
@@ -33,7 +33,6 @@ struct Node_1
 : public CGAL::Compact_container_base
 {
   Node_1() {}
-  Node_1(const Node_1& o) : time_stamp_(o.time_stamp_) {}
   bool operator==(const Node_1 &) const { return true; }
   bool operator!=(const Node_1 &) const { return false; }
   bool operator< (const Node_1 &) const { return false; }
@@ -61,14 +60,14 @@ public:
   int      rnd;
 
   Node_2()
-  : p(NULL), rnd(CGAL::get_default_random().get_int(0, 100)) {}
+  : p(nullptr), rnd(CGAL::get_default_random().get_int(0, 100)) {}
 
   bool operator==(const Node_2 &n) const { return rnd == n.rnd; }
   bool operator!=(const Node_2 &n) const { return rnd != n.rnd; }
   bool operator< (const Node_2 &n) const { return rnd <  n.rnd; }
 
   void *   for_compact_container() const { return p_cc; }
-  void * & for_compact_container()       { return p_cc; }
+  void for_compact_container(void *p) { p_cc = p; }
 };
 
 template < class Cont >
@@ -89,11 +88,6 @@ public:
     : m_values(values), m_cont(cont), m_iterators(iterators)
   {}
 
-  Insert_in_CCC_functor(const Insert_in_CCC_functor &other)
-    : m_values(other.m_values), m_cont(other.m_cont),
-      m_iterators(other.m_iterators)
-  {}
-
   void operator() (const tbb::blocked_range<size_t>& r) const
   {
     for( size_t i = r.begin() ; i != r.end() ; ++i)
@@ -118,11 +112,6 @@ public:
     : m_cont(cont), m_iterators(iterators)
   {}
 
-  Erase_in_CCC_functor(const Erase_in_CCC_functor &other)
-    : m_cont(other.m_cont),
-      m_iterators(other.m_iterators)
-  {}
-
   void operator() (const tbb::blocked_range<size_t>& r) const
   {
     for( size_t i = r.begin() ; i != r.end() ; ++i)
@@ -149,19 +138,13 @@ public:
     m_free_elements(free_elements), m_num_erasures(num_erasures)
   {}
 
-  Insert_and_erase_in_CCC_functor(const Insert_and_erase_in_CCC_functor &other)
-    : m_values(other.m_values), m_cont(other.m_cont),
-      m_iterators(other.m_iterators), m_free_elements(other.m_free_elements),
-      m_num_erasures(other.m_num_erasures)
-  {}
-
   void operator() (const tbb::blocked_range<size_t>& r) const
   {
     for( size_t i = r.begin() ; i != r.end() ; ++i)
     {
       m_iterators[i] = m_cont.insert(m_values[i]);
       // Random-pick an element to erase
-      int index_to_erase = rand() % m_values.size();
+      auto index_to_erase = rand() % m_values.size();
       // If it exists
       bool comparand = false;
       if (m_free_elements[index_to_erase].compare_exchange_weak(comparand, true) )
@@ -183,6 +166,10 @@ private:
 template < class Cont >
 void test(const Cont &)
 {
+  static_assert(std::is_nothrow_move_constructible<Cont>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Cont>::value,
+                "move assignment is missing");
   // Testing if all types are provided.
 
   typename Cont::value_type              t0;
diff --git a/Scale_space_reconstruction_3/examples/Scale_space_reconstruction_3/CMakeLists.txt b/Scale_space_reconstruction_3/examples/Scale_space_reconstruction_3/CMakeLists.txt
index e1bfb24bc41..b6b1e1a3ba1 100644
--- a/Scale_space_reconstruction_3/examples/Scale_space_reconstruction_3/CMakeLists.txt
+++ b/Scale_space_reconstruction_3/examples/Scale_space_reconstruction_3/CMakeLists.txt
@@ -13,26 +13,28 @@ if ( CGAL_FOUND )
 
   if( ACTIVATE_CONCURRENCY )
     find_package( TBB )
-    if( NOT TBB_FOUND )
+    include(CGAL_TBB_support)
+    if( NOT TARGET CGAL::TBB_support )
       message( STATUS "NOTICE: Intel TBB NOT found! The example is faster if TBB is linked." )
     endif()
   endif()
 
   find_package( Eigen3 3.1.0 )
-  if( EIGEN3_FOUND )
+  include(CGAL_Eigen_support)
+  if( TARGET CGAL::Eigen_support )
     create_single_source_cgal_program( "scale_space.cpp" )
-    CGAL_target_use_Eigen(scale_space)
+    target_link_libraries(scale_space PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "scale_space_incremental.cpp" )
-    CGAL_target_use_Eigen(scale_space_incremental)
+    target_link_libraries(scale_space_incremental PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "scale_space_manifold.cpp" )
-    CGAL_target_use_Eigen(scale_space_manifold)
+    target_link_libraries(scale_space_manifold PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "scale_space_advancing_front.cpp" )
-    CGAL_target_use_Eigen(scale_space_advancing_front)
-    if(ACTIVATE_CONCURRENCY AND TBB_FOUND)
-      CGAL_target_use_TBB(scale_space)
-      CGAL_target_use_TBB(scale_space_incremental)
-      CGAL_target_use_TBB(scale_space_manifold)
-      CGAL_target_use_TBB(scale_space_advancing_front)
+    target_link_libraries(scale_space_advancing_front PUBLIC CGAL::Eigen_support)
+    if(ACTIVATE_CONCURRENCY AND TARGET CGAL::TBB_support)
+      target_link_libraries(scale_space PUBLIC CGAL::TBB_support)
+      target_link_libraries(scale_space_incremental PUBLIC CGAL::TBB_support)
+      target_link_libraries(scale_space_manifold PUBLIC CGAL::TBB_support)
+      target_link_libraries(scale_space_advancing_front PUBLIC CGAL::TBB_support)
     endif()
   else()
     message( STATUS "NOTICE: The example needs Eigen 3.1 (or greater) and will not be compiled." )
diff --git a/Shape_detection/benchmark/Shape_detection/CMakeLists.txt b/Shape_detection/benchmark/Shape_detection/CMakeLists.txt
index e89abfcbdf8..0e8d4b74cf0 100644
--- a/Shape_detection/benchmark/Shape_detection/CMakeLists.txt
+++ b/Shape_detection/benchmark/Shape_detection/CMakeLists.txt
@@ -14,13 +14,14 @@ if(CGAL_FOUND)
 
   # Use Eigen.
   find_package(Eigen3 3.1.0 QUIET) # (3.1.0 or greater)
-  if(EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if(TARGET CGAL::Eigen_support)
     create_single_source_cgal_program(
       "benchmark_region_growing_on_point_set_2.cpp")
-    CGAL_target_use_Eigen(benchmark_region_growing_on_point_set_2)
+    target_link_libraries(benchmark_region_growing_on_point_set_2 PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program(
       "benchmark_region_growing_on_point_set_3.cpp")
-    CGAL_target_use_Eigen(benchmark_region_growing_on_point_set_3)
+    target_link_libraries(benchmark_region_growing_on_point_set_3 PUBLIC CGAL::Eigen_support)
   endif()
 
 else()
diff --git a/Shape_detection/doc/Shape_detection/PackageDescription.txt b/Shape_detection/doc/Shape_detection/PackageDescription.txt
index 5ace984878d..52001fe612e 100644
--- a/Shape_detection/doc/Shape_detection/PackageDescription.txt
+++ b/Shape_detection/doc/Shape_detection/PackageDescription.txt
@@ -59,12 +59,12 @@ Deprecated components.
 
 \cgalPkgSummaryBegin
 \cgalPkgAuthors{Sven Oesau, Yannick Verdie, Clément Jamin, Pierre Alliez, Florent Lafarge, Simon Giraudot, Thien Hoang, and Dmitry Anisimov}
-\cgalPkgDesc{This CGAL package implements the Efficient RANSAC (RANdom SAmple Consensus) approach
+\cgalPkgDesc{This package implements the Efficient RANSAC (RANdom SAmple Consensus) approach
 for detecting arbitrary shapes in an unorganized point set with unoriented normals
 and the Region Growing approach for detecting shapes in a set of arbitrary items.
 With the Efficient RANSAC approach, five canonical shapes can be detected: planes, spheres,
 cylinders, cones, and tori. Additional shapes can be detected, given a custom shape class by the user.
-For the Region Growing approach, CGAL provides three particular shape detection components:
+For the Region Growing approach, this package provides three particular shape detection components:
 detecting lines in a 2D point set, detecting planes in a 3D point set, and detecting planes
 on a polygon mesh.}
 \cgalPkgManuals{Chapter_Shape_Detection, PkgShapeDetectionRef}
diff --git a/Shape_detection/examples/Shape_detection/CMakeLists.txt b/Shape_detection/examples/Shape_detection/CMakeLists.txt
index be7c4667d6d..b012e3a0256 100644
--- a/Shape_detection/examples/Shape_detection/CMakeLists.txt
+++ b/Shape_detection/examples/Shape_detection/CMakeLists.txt
@@ -14,7 +14,8 @@ if(CGAL_FOUND)
 
   # Use Eigen.
   find_package(Eigen3 3.1.0 QUIET) # (3.1.0 or greater)
-  if(EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if(TARGET CGAL::Eigen_support)
     create_single_source_cgal_program(
       "efficient_RANSAC_basic.cpp")
     create_single_source_cgal_program(
@@ -43,7 +44,7 @@ if(CGAL_FOUND)
         region_growing_on_polygon_mesh
         region_growing_with_custom_classes
         shape_detection_basic_deprecated)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endforeach()
 
   endif()
diff --git a/Shape_detection/test/Shape_detection/CMakeLists.txt b/Shape_detection/test/Shape_detection/CMakeLists.txt
index 2effc7dd265..b804d1014f2 100644
--- a/Shape_detection/test/Shape_detection/CMakeLists.txt
+++ b/Shape_detection/test/Shape_detection/CMakeLists.txt
@@ -14,6 +14,7 @@ if(CGAL_FOUND)
 
   # Use Eigen.
   find_package(Eigen3 3.1.0 QUIET) # (3.1.0 or greater)
+  include(CGAL_Eigen_support)
   if(EIGEN3_FOUND)
     create_single_source_cgal_program(
       "test_region_growing_basic.cpp")
@@ -43,7 +44,7 @@ if(CGAL_FOUND)
         test_region_growing_on_point_set_3_with_sorting
         test_region_growing_on_polygon_mesh_with_sorting
         test_region_growing_on_degenerated_mesh)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endforeach()
 
   endif()
diff --git a/Solver_interface/examples/Solver_interface/CMakeLists.txt b/Solver_interface/examples/Solver_interface/CMakeLists.txt
index fbbea89f568..d6f2c10833a 100644
--- a/Solver_interface/examples/Solver_interface/CMakeLists.txt
+++ b/Solver_interface/examples/Solver_interface/CMakeLists.txt
@@ -12,32 +12,35 @@ if ( CGAL_FOUND )
 
   # Use Eigen
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
+  include(CGAL_Eigen_support)
 
-  if (EIGEN3_FOUND)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "singular_value_decomposition.cpp" )
-    CGAL_target_use_Eigen(singular_value_decomposition)
+    target_link_libraries(singular_value_decomposition PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "sparse_solvers.cpp" )
-    CGAL_target_use_Eigen(sparse_solvers)
+    target_link_libraries(sparse_solvers PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "diagonalize_matrix.cpp" )
-    CGAL_target_use_Eigen(diagonalize_matrix)
+    target_link_libraries(diagonalize_matrix PUBLIC CGAL::Eigen_support)
   endif()
 
   create_single_source_cgal_program( "mixed_integer_program.cpp" )
 
   find_package( SCIP QUIET)
+  include(CGAL_SCIP_support)
 
-  if (SCIP_FOUND)
+  if (TARGET CGAL::SCIP_support)
 
-    CGAL_target_use_SCIP(mixed_integer_program)
+    target_link_libraries(mixed_integer_program PUBLIC CGAL::SCIP_support)
     message("SCIP found and used")
 
   else()
 
-      find_package( GLPK QUIET)
+    find_package( GLPK QUIET)
+    include(CGAL_GLPK_support)
 
-      if (GLPK_FOUND)
+      if (TARGET CGAL::GLPK_support)
 
-        CGAL_target_use_GLPK(mixed_integer_program)
+        target_link_libraries(mixed_integer_program PUBLIC CGAL::GLPK_support)
         message("GLPK found and used")
 
       else()
@@ -54,4 +57,3 @@ else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Spatial_searching/benchmark/Spatial_searching/CMakeLists.txt b/Spatial_searching/benchmark/Spatial_searching/CMakeLists.txt
index 010a9bc992f..e2bb99bb3f6 100644
--- a/Spatial_searching/benchmark/Spatial_searching/CMakeLists.txt
+++ b/Spatial_searching/benchmark/Spatial_searching/CMakeLists.txt
@@ -13,6 +13,7 @@ if ( CGAL_FOUND )
 include(${CGAL_USE_FILE})
 
 find_package(Eigen3 3.1.91) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
   include_directories (BEFORE "include")
 
@@ -45,7 +46,7 @@ find_package(Eigen3 3.1.91) #(requires 3.2.0 or greater)
       nn3nanoflan
       sizeof
       deque)
-    CGAL_target_use_Eigen(${target})
+    target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
   endforeach()
 
 else()
@@ -53,4 +54,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Spatial_searching/examples/Spatial_searching/CMakeLists.txt b/Spatial_searching/examples/Spatial_searching/CMakeLists.txt
index 8cf10aa93f4..6ea87500e55 100644
--- a/Spatial_searching/examples/Spatial_searching/CMakeLists.txt
+++ b/Spatial_searching/examples/Spatial_searching/CMakeLists.txt
@@ -18,6 +18,7 @@ if ( NOT CGAL_FOUND )
 endif()
 
 find_package(Eigen3 3.1.91) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
 if (MSVC)
     # Turn off VC++ warning
@@ -62,13 +63,13 @@ create_single_source_cgal_program( "weighted_Minkowski_distance.cpp" )
 
 
 
-if (EIGEN3_FOUND)
+if (TARGET CGAL::Eigen_support)
 
   create_single_source_cgal_program( "fuzzy_range_query.cpp" )
-  CGAL_target_use_Eigen(fuzzy_range_query)
+  target_link_libraries(fuzzy_range_query PUBLIC CGAL::Eigen_support)
 
   create_single_source_cgal_program( "general_neighbor_searching.cpp" )
-  CGAL_target_use_Eigen(general_neighbor_searching)
+  target_link_libraries(general_neighbor_searching PUBLIC CGAL::Eigen_support)
 
 else()
 
@@ -78,9 +79,10 @@ else()
 endif()
 
 find_package( TBB QUIET )
-if(TBB_FOUND)
+include(CGAL_TBB_support)
+if(TARGET CGAL::TBB_support)
   create_single_source_cgal_program( "parallel_kdtree.cpp" )
-  cgal_target_use_TBB(parallel_kdtree)
+  target_link_libraries(parallel_kdtree PUBLIC CGAL::TBB_support)
 else()
   message(STATUS "parallel_kdtree.cpp requires TBB and will not be compiled")
 endif()
diff --git a/Spatial_sorting/examples/Spatial_sorting/CMakeLists.txt b/Spatial_sorting/examples/Spatial_sorting/CMakeLists.txt
index f865c8028c2..25197170b29 100644
--- a/Spatial_sorting/examples/Spatial_sorting/CMakeLists.txt
+++ b/Spatial_sorting/examples/Spatial_sorting/CMakeLists.txt
@@ -16,13 +16,12 @@ if ( CGAL_FOUND )
   endforeach()
 
   find_package( TBB QUIET )
-  if( TBB_FOUND )
-    include( CGAL_target_use_TBB )
-    CGAL_target_use_TBB( parallel_spatial_sort_3 )
+  include(CGAL_TBB_support)
+  if( TARGET CGAL::TBB_support )
+    target_link_libraries( parallel_spatial_sort_3 PUBLIC CGAL::TBB_support)
  endif()
 else()
 
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Spatial_sorting/include/CGAL/spatial_sort.h b/Spatial_sorting/include/CGAL/spatial_sort.h
index aa38be26af8..90dd07bd966 100644
--- a/Spatial_sorting/include/CGAL/spatial_sort.h
+++ b/Spatial_sorting/include/CGAL/spatial_sort.h
@@ -111,7 +111,7 @@ void spatial_sort (RandomAccessIterator begin, RandomAccessIterator end,
   typedef std::iterator_traits<RandomAccessIterator> ITraits;
   typedef typename ITraits::value_type               value_type;
 
-  internal::spatial_sort<ConcurrencyTag>(begin, end, k, policy, static_cast<value_type *> (0),
+  internal::spatial_sort<ConcurrencyTag>(begin, end, k, policy, static_cast<value_type *> (nullptr),
                                          threshold_hilbert,threshold_multiscale,ratio);
 }
 
diff --git a/Spatial_sorting/test/Spatial_sorting/CMakeLists.txt b/Spatial_sorting/test/Spatial_sorting/CMakeLists.txt
index 8213186a4b0..437508bf629 100644
--- a/Spatial_sorting/test/Spatial_sorting/CMakeLists.txt
+++ b/Spatial_sorting/test/Spatial_sorting/CMakeLists.txt
@@ -13,14 +13,13 @@ if ( CGAL_FOUND )
   create_single_source_cgal_program( "test_multiscale.cpp" )
 
   find_package (TBB QUIET)
-  if( TBB_FOUND )
-    include( CGAL_target_use_TBB )
-    CGAL_target_use_TBB( test_hilbert )
-  endif( TBB_FOUND )
+  include(CGAL_TBB_support)
+  if( TARGET CGAL::TBB_support )
+    target_link_libraries( test_hilbert PUBLIC CGAL::TBB_support )
+  endif()
 
 else()
 
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh/include/CGAL/Surface_mesh/Surface_mesh.h b/Surface_mesh/include/CGAL/Surface_mesh/Surface_mesh.h
index 0c076db5340..ea1cabc80d1 100644
--- a/Surface_mesh/include/CGAL/Surface_mesh/Surface_mesh.h
+++ b/Surface_mesh/include/CGAL/Surface_mesh/Surface_mesh.h
@@ -1127,6 +1127,8 @@ public:
   }
 
     /// removes all vertices, halfedge, edges and faces. Collects garbage and clears all properties.
+    ///
+    /// After calling this method, the object is the same as a newly constructed object. The additional properties (such as normal vectors) are also removed and must thus be re-added if needed.
     void clear();
 
 
diff --git a/Surface_mesh_approximation/examples/Surface_mesh_approximation/CMakeLists.txt b/Surface_mesh_approximation/examples/Surface_mesh_approximation/CMakeLists.txt
index aa73bcd3807..c73ab50c135 100644
--- a/Surface_mesh_approximation/examples/Surface_mesh_approximation/CMakeLists.txt
+++ b/Surface_mesh_approximation/examples/Surface_mesh_approximation/CMakeLists.txt
@@ -28,7 +28,8 @@ endif()
 
 # Use Eigen (for PCA)
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -39,20 +40,19 @@ endif()
 include( CGAL_CreateSingleSourceCGALProgram )
 
 create_single_source_cgal_program( "vsa_approximation_2_example.cpp" )
-CGAL_target_use_Eigen(vsa_approximation_2_example)
+target_link_libraries(vsa_approximation_2_example PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_approximation_example.cpp" )
-CGAL_target_use_Eigen(vsa_approximation_example)
+target_link_libraries(vsa_approximation_example PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_class_interface_example.cpp" )
-CGAL_target_use_Eigen(vsa_class_interface_example)
+target_link_libraries(vsa_class_interface_example PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_isotropic_metric_example.cpp" )
-CGAL_target_use_Eigen(vsa_isotropic_metric_example)
+target_link_libraries(vsa_isotropic_metric_example PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_segmentation_example.cpp" )
-CGAL_target_use_Eigen(vsa_segmentation_example)
+target_link_libraries(vsa_segmentation_example PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_simple_approximation_example.cpp" )
-CGAL_target_use_Eigen(vsa_simple_approximation_example)
-
+target_link_libraries(vsa_simple_approximation_example PUBLIC CGAL::Eigen_support)
diff --git a/Surface_mesh_approximation/test/Surface_mesh_approximation/CMakeLists.txt b/Surface_mesh_approximation/test/Surface_mesh_approximation/CMakeLists.txt
index a41a41f1996..9548e5ac986 100644
--- a/Surface_mesh_approximation/test/Surface_mesh_approximation/CMakeLists.txt
+++ b/Surface_mesh_approximation/test/Surface_mesh_approximation/CMakeLists.txt
@@ -29,7 +29,8 @@ endif()
 
 # Use Eigen (for PCA)
 find_package(Eigen3 3.1.0 REQUIRED) #(3.1.0 or greater)
-if (NOT EIGEN3_FOUND)
+include(CGAL_Eigen_support)
+if (NOT TARGET CGAL::Eigen_support)
   message(STATUS "This project requires the Eigen library, and will not be compiled.")
   return()
 endif()
@@ -41,30 +42,28 @@ endif()
 include( CGAL_CreateSingleSourceCGALProgram )
 
 create_single_source_cgal_program( "vsa_class_interface_test.cpp" )
-CGAL_target_use_Eigen(vsa_class_interface_test)
+target_link_libraries(vsa_class_interface_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_correctness_test.cpp" )
-CGAL_target_use_Eigen(vsa_correctness_test)
+target_link_libraries(vsa_correctness_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_error_decrease_test.cpp" )
-CGAL_target_use_Eigen(vsa_error_decrease_test)
+target_link_libraries(vsa_error_decrease_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_kernel_test.cpp" )
-CGAL_target_use_Eigen(vsa_kernel_test)
+target_link_libraries(vsa_kernel_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_approximation_test.cpp" )
-CGAL_target_use_Eigen(vsa_approximation_test)
+target_link_libraries(vsa_approximation_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_segmentation_test.cpp" )
-CGAL_target_use_Eigen(vsa_segmentation_test)
+target_link_libraries(vsa_segmentation_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_meshing_manifold_test.cpp" )
-CGAL_target_use_Eigen(vsa_meshing_manifold_test)
+target_link_libraries(vsa_meshing_manifold_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_metric_test.cpp" )
-CGAL_target_use_Eigen(vsa_metric_test)
+target_link_libraries(vsa_metric_test PUBLIC CGAL::Eigen_support)
 
 create_single_source_cgal_program( "vsa_teleportation_test.cpp" )
-CGAL_target_use_Eigen(vsa_teleportation_test)
-
-
+target_link_libraries(vsa_teleportation_test PUBLIC CGAL::Eigen_support)
diff --git a/Surface_mesh_deformation/benchmark/Surface_mesh_deformation/optimal_rotation/CMakeLists.txt b/Surface_mesh_deformation/benchmark/Surface_mesh_deformation/optimal_rotation/CMakeLists.txt
index 4d24c1d593c..bce18be7df6 100644
--- a/Surface_mesh_deformation/benchmark/Surface_mesh_deformation/optimal_rotation/CMakeLists.txt
+++ b/Surface_mesh_deformation/benchmark/Surface_mesh_deformation/optimal_rotation/CMakeLists.txt
@@ -10,13 +10,13 @@ if ( CGAL_FOUND )
   include(${CGAL_USE_FILE})
 
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "benchmark_for_concept_models.cpp" )
-    CGAL_target_use_Eigen(benchmark_for_concept_models)
+    target_link_libraries(benchmark_for_concept_models PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "This program requires the Eigen library, version 3.1 or later and will not be compiled.")
   endif()
 else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 endif()
-
diff --git a/Surface_mesh_deformation/demo/Surface_mesh_deformation/CMakeLists.txt b/Surface_mesh_deformation/demo/Surface_mesh_deformation/CMakeLists.txt
index b17f5995d32..daabda6ac44 100644
--- a/Surface_mesh_deformation/demo/Surface_mesh_deformation/CMakeLists.txt
+++ b/Surface_mesh_deformation/demo/Surface_mesh_deformation/CMakeLists.txt
@@ -17,9 +17,10 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.1.91) #(requires 3.2.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "deform_mesh_for_botsch08_format.cpp" )
-    CGAL_target_use_Eigen(deform_mesh_for_botsch08_format)
+    target_link_libraries(deform_mesh_for_botsch08_format PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "NOTICE: This program requires the Eigen library, version 3.2 or later and will not be compiled.")
   endif()
@@ -28,4 +29,3 @@ else()
     message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_deformation/examples/Surface_mesh_deformation/CMakeLists.txt b/Surface_mesh_deformation/examples/Surface_mesh_deformation/CMakeLists.txt
index ca146f90433..f60163d11be 100644
--- a/Surface_mesh_deformation/examples/Surface_mesh_deformation/CMakeLists.txt
+++ b/Surface_mesh_deformation/examples/Surface_mesh_deformation/CMakeLists.txt
@@ -12,7 +12,8 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.1.91) #(requires 3.2.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "all_roi_assign_example.cpp" )
     create_single_source_cgal_program( "all_roi_assign_example_custom_polyhedron.cpp" )
     create_single_source_cgal_program( "all_roi_assign_example_Surface_mesh.cpp" )
@@ -31,15 +32,14 @@ if ( CGAL_FOUND )
         k_ring_roi_translate_rotate_example
         k_ring_roi_translate_rotate_Surface_mesh
         deform_mesh_for_botsch08_format_sre_arap)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endforeach()
 
     find_package( OpenMesh QUIET )
     if ( OpenMesh_FOUND )
     include( UseOpenMesh )
       create_single_source_cgal_program( "all_roi_assign_example_with_OpenMesh.cpp" )
-      target_link_libraries( all_roi_assign_example_with_OpenMesh PRIVATE ${OPENMESH_LIBRARIES} )
-      CGAL_target_use_Eigen(all_roi_assign_example_with_OpenMesh)
+      target_link_libraries( all_roi_assign_example_with_OpenMesh PRIVATE ${OPENMESH_LIBRARIES} CGAL::Eigen_support)
     else()
       message(STATUS "Example that use OpenMesh will not be compiled.")
     endif()
@@ -52,4 +52,3 @@ else()
     message(STATUS "NOTICE: These exmaples require the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_deformation/test/Surface_mesh_deformation/CMakeLists.txt b/Surface_mesh_deformation/test/Surface_mesh_deformation/CMakeLists.txt
index 05da9a51cf7..624cef733bb 100644
--- a/Surface_mesh_deformation/test/Surface_mesh_deformation/CMakeLists.txt
+++ b/Surface_mesh_deformation/test/Surface_mesh_deformation/CMakeLists.txt
@@ -12,20 +12,20 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.1.91) #(requires 3.2.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "Cactus_deformation_session.cpp" )
-    CGAL_target_use_Eigen(Cactus_deformation_session)
+    target_link_libraries(Cactus_deformation_session PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "Cactus_performance_test.cpp" )
-    CGAL_target_use_Eigen(Cactus_performance_test)
+    target_link_libraries(Cactus_performance_test PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "Symmetry_test.cpp" )
-    CGAL_target_use_Eigen(Symmetry_test)
+    target_link_libraries(Symmetry_test PUBLIC CGAL::Eigen_support)
 
     find_package( OpenMesh QUIET )
     if ( OpenMesh_FOUND )
     include( UseOpenMesh )
       create_single_source_cgal_program( "Cactus_deformation_session_OpenMesh.cpp" )
-      CGAL_target_use_Eigen(Cactus_deformation_session_OpenMesh)
-      target_link_libraries( Cactus_deformation_session_OpenMesh PRIVATE ${OPENMESH_LIBRARIES} )
+      target_link_libraries( Cactus_deformation_session_OpenMesh PRIVATE ${OPENMESH_LIBRARIES} CGAL::Eigen_support)
     else()
       message(STATUS "Example that use OpenMesh will not be compiled.")
     endif()
@@ -37,4 +37,3 @@ else()
     message(STATUS "NOTICE: These tests require the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_parameterization/examples/Surface_mesh_parameterization/CMakeLists.txt b/Surface_mesh_parameterization/examples/Surface_mesh_parameterization/CMakeLists.txt
index 185aacb9503..eab97c84ecb 100644
--- a/Surface_mesh_parameterization/examples/Surface_mesh_parameterization/CMakeLists.txt
+++ b/Surface_mesh_parameterization/examples/Surface_mesh_parameterization/CMakeLists.txt
@@ -12,7 +12,8 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     # Executables that require Eigen 3.1
 
 # ------------------------------------------------------------------
@@ -51,29 +52,28 @@ if ( CGAL_FOUND )
 # ------------------------------------------------------------------
 
     create_single_source_cgal_program( "discrete_authalic.cpp" )
-    CGAL_target_use_Eigen(discrete_authalic)
+    target_link_libraries(discrete_authalic PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "lscm.cpp" )
-    CGAL_target_use_Eigen(lscm)
+    target_link_libraries(lscm PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "orbifold.cpp" )
-    CGAL_target_use_Eigen(orbifold)
+    target_link_libraries(orbifold PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "seam_Polyhedron_3.cpp" )
-    CGAL_target_use_Eigen(seam_Polyhedron_3)
+    target_link_libraries(seam_Polyhedron_3 PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "simple_parameterization.cpp" )
-    CGAL_target_use_Eigen(simple_parameterization)
+    target_link_libraries(simple_parameterization PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "square_border_parameterizer.cpp" )
-    CGAL_target_use_Eigen(square_border_parameterizer)
+    target_link_libraries(square_border_parameterizer PUBLIC CGAL::Eigen_support)
 
     if(SuiteSparse_FOUND)
       target_link_libraries(orbifold PRIVATE ${SuiteSparse_LIBRARIES})
     endif()
 
-  else(EIGEN3_FOUND)
+  else()
     message(STATUS "NOTICE: The examples require Eigen 3.1 (or greater) and will not be compiled.")
-  endif(EIGEN3_FOUND)
+  endif()
 
 else()
 
   message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_parameterization/test/Surface_mesh_parameterization/CMakeLists.txt b/Surface_mesh_parameterization/test/Surface_mesh_parameterization/CMakeLists.txt
index 401f37978b4..7141d3fef9a 100644
--- a/Surface_mesh_parameterization/test/Surface_mesh_parameterization/CMakeLists.txt
+++ b/Surface_mesh_parameterization/test/Surface_mesh_parameterization/CMakeLists.txt
@@ -13,16 +13,16 @@ if ( CGAL_FOUND )
 
 
   find_package(Eigen3 3.1.0) #(requires 3.1.0 or greater)
-  if(EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if(TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "extensive_parameterization_test.cpp" )
-    CGAL_target_use_Eigen(extensive_parameterization_test)
-  else(EIGEN3_FOUND)
+    target_link_libraries(extensive_parameterization_test PUBLIC CGAL::Eigen_support)
+  else()
     message(STATUS "NOTICE: The tests require Eigen 3.1 (or greater) and will not be compiled.")
-  endif(EIGEN3_FOUND)
+  endif()
 
 else()
 
   message(STATUS "NOTICE: This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_shortest_path/include/CGAL/Surface_mesh_shortest_path/Surface_mesh_shortest_path.h b/Surface_mesh_shortest_path/include/CGAL/Surface_mesh_shortest_path/Surface_mesh_shortest_path.h
index 86316179c41..6d24ecfcab3 100644
--- a/Surface_mesh_shortest_path/include/CGAL/Surface_mesh_shortest_path/Surface_mesh_shortest_path.h
+++ b/Surface_mesh_shortest_path/include/CGAL/Surface_mesh_shortest_path/Surface_mesh_shortest_path.h
@@ -257,12 +257,12 @@ public:
       return temp;
     }
 
-    bool operator==(const Source_point_iterator& other)
+    bool operator==(const Source_point_iterator& other) const
     {
       return m_iterator == other.m_iterator;
     }
 
-    bool operator!=(const Source_point_iterator& other)
+    bool operator!=(const Source_point_iterator& other) const
     {
       return m_iterator != other.m_iterator;
     }
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/CMakeLists.txt b/Surface_mesh_simplification/examples/Surface_mesh_simplification/CMakeLists.txt
index cb06fb9d434..bfd216d1e80 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/CMakeLists.txt
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/CMakeLists.txt
@@ -43,9 +43,10 @@ create_single_source_cgal_program( "edge_collapse_bounded_normal_change.cpp" )
 create_single_source_cgal_program( "edge_collapse_visitor_surface_mesh.cpp" )
 
 find_package(Eigen3 3.1.0 QUIET) #(3.1.0 or greater)
-if( Eigen3_FOUND )
+include(CGAL_Eigen_support)
+if( TARGET CGAL::Eigen_support )
   create_single_source_cgal_program( "edge_collapse_garland_heckbert.cpp" )
-  CGAL_target_use_Eigen(edge_collapse_garland_heckbert)
+  target_link_libraries(edge_collapse_garland_heckbert PUBLIC CGAL::Eigen_support)
 else ()
   message(STATUS "Garland-Heckbert polices require the Eigen library, which has not been found; related examples will not be compiled.")
 endif()
diff --git a/Surface_mesh_skeletonization/benchmark/Surface_mesh_skeletonization/CMakeLists.txt b/Surface_mesh_skeletonization/benchmark/Surface_mesh_skeletonization/CMakeLists.txt
index 0fb1f28c09d..b5522d61809 100644
--- a/Surface_mesh_skeletonization/benchmark/Surface_mesh_skeletonization/CMakeLists.txt
+++ b/Surface_mesh_skeletonization/benchmark/Surface_mesh_skeletonization/CMakeLists.txt
@@ -35,17 +35,17 @@ endif()
 
 # include for local package
 find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+include(CGAL_Eigen_support)
 
-if(NOT EIGEN3_FOUND)
+if(NOT TARGET CGAL::Eigen_support)
   message(STATUS "NOTICE: Eigen 3.2 (or greater) is not found.")
-endif(NOT EIGEN3_FOUND)
+endif()
 
 
 # Creating entries for all .cpp/.C files with "main" routine
 # ##########################################################
 
 create_single_source_cgal_program( "solver_benchmark.cpp" )
-CGAL_target_use_Eigen(solver_benchmark)
+target_link_libraries(solver_benchmark PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "mcf_scale_invariance.cpp" )
-CGAL_target_use_Eigen(mcf_scale_invariance)
-
+target_link_libraries(mcf_scale_invariance PUBLIC CGAL::Eigen_support)
diff --git a/Surface_mesh_skeletonization/examples/Surface_mesh_skeletonization/CMakeLists.txt b/Surface_mesh_skeletonization/examples/Surface_mesh_skeletonization/CMakeLists.txt
index d3f29d30dc3..e5ee181c4d3 100644
--- a/Surface_mesh_skeletonization/examples/Surface_mesh_skeletonization/CMakeLists.txt
+++ b/Surface_mesh_skeletonization/examples/Surface_mesh_skeletonization/CMakeLists.txt
@@ -12,8 +12,9 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+  include(CGAL_Eigen_support)
 
-  if(EIGEN3_FOUND)
+  if(TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "simple_mcfskel_example.cpp" )
     create_single_source_cgal_program( "simple_mcfskel_sm_example.cpp" )
     create_single_source_cgal_program( "simple_mcfskel_LCC_example.cpp" )
@@ -29,7 +30,7 @@ if ( CGAL_FOUND )
         MCF_Skeleton_sm_example
         MCF_Skeleton_LCC_example
         segmentation_example)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endforeach()
   else()
     message(STATUS "These programs require the Eigen library (3.2 or greater), and will not be compiled.")
@@ -40,4 +41,3 @@ else()
   message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_skeletonization/test/Surface_mesh_skeletonization/CMakeLists.txt b/Surface_mesh_skeletonization/test/Surface_mesh_skeletonization/CMakeLists.txt
index fd313cbf499..29adc5293fe 100644
--- a/Surface_mesh_skeletonization/test/Surface_mesh_skeletonization/CMakeLists.txt
+++ b/Surface_mesh_skeletonization/test/Surface_mesh_skeletonization/CMakeLists.txt
@@ -12,12 +12,13 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.2.0) #(requires 3.2.0 or greater)
+  include(CGAL_Eigen_support)
 
-  if(EIGEN3_FOUND)
+  if(TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "MCF_Skeleton_test.cpp" )
-    CGAL_target_use_Eigen(MCF_Skeleton_test)
+    target_link_libraries(MCF_Skeleton_test PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "skeleton_connectivity_test.cpp" )
-    CGAL_target_use_Eigen(skeleton_connectivity_test)
+    target_link_libraries(skeleton_connectivity_test PUBLIC CGAL::Eigen_support)
   else()
     message(STATUS "These tests require the Eigen library (3.2 or greater), and will not be compiled.")
   endif()
@@ -26,4 +27,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Curves_on_surface_topology.h b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Curves_on_surface_topology.h
index ada0f528d73..b37e714ee5e 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Curves_on_surface_topology.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Curves_on_surface_topology.h
@@ -4,7 +4,7 @@ namespace Surface_mesh_topology {
   /*!
     \ingroup PkgSurfaceMeshTopologyClasses
 
-    The class `Curves_on_surface_topology` provides methods to compute shortest non contracible cycles and to test homotopy on paths. Each object of this class is constructed from an external mesh, either a \ref CombinatorialMap "2D combinatorial map" or a model of a FaceGraph. It maintains a correspondence between this mesh and an internal representation, computed the first time an homotopy test is called. The user must not modify the input surface as long as homotopy tests are performed with this `Curves_on_surface_topology`.
+    The class `Curves_on_surface_topology` provides methods to compute shortest non contractible cycles and to test homotopy on paths. Each object of this class is constructed from an external mesh, either a \ref CombinatorialMap "2D combinatorial map" or a model of a FaceGraph. It maintains a correspondence between this mesh and an internal representation, computed the first time an homotopy test is called. The user must not modify the input surface as long as homotopy tests are performed with this `Curves_on_surface_topology`.
 
     \tparam Mesh a model of `CombinatorialMap` or of `FaceGraph`
   */
@@ -14,7 +14,7 @@ namespace Surface_mesh_topology {
   public:
 
     /*!
-      %halfedge_descriptor type. A handle to `Dart` for combinatorial/generalized maps, or a halfedge descriptor for models of the `FaceGraph` concept.
+      A handle to `Dart` for combinatorial/generalized maps, or a halfedge descriptor for models of the `FaceGraph` concept.
     */
     typedef unspecified_type halfedge_descriptor;
 
@@ -53,7 +53,7 @@ namespace Surface_mesh_topology {
     template <class WeightFunctor=Unit_weight_functor>
     Path_on_surface<Mesh> compute_shortest_non_contractible_cycle_with_base_point(halfedge_descriptor dh, const WeightFunctor& wf=WeightFunctor()) const;
 
-    /*! returns a vector of darts representing a non-contractible curve with a minimal number of intersection with the graph of the mesh. This curve can be decribed by the alternating sequence of faces and vertices it goes through, so that each dart in the returned vector belongs to both a face and the next vertex in the alternating sequence. (Here, faces and vertices are viewed as subsets of darts.) The size of the returned vector is the face width of the mesh.
+    /*! returns a vector of darts representing a non-contractible curve with a minimal number of intersection with the graph of the mesh. This curve can be described by the alternating sequence of faces and vertices it goes through, so that each dart in the returned vector belongs to both a face and the next vertex in the alternating sequence. (Here, faces and vertices are viewed as subsets of darts.) The size of the returned vector is the face width of the mesh.
      */
     std::vector<halfedge_descriptor> compute_face_width() const;
   };
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Path_on_surface.h b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Path_on_surface.h
index 0a3b1f99806..bd7ead4deda 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Path_on_surface.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Path_on_surface.h
@@ -13,7 +13,7 @@ namespace Surface_mesh_topology {
   {
   public:
     /*!
-      %halfedge_descriptor type. A handle to `Dart` for combinatorial/generalized maps, or a halfedge descriptor for models of the `FaceGraph` concept.
+      A handle to `Dart` for combinatorial/generalized maps, or a halfedge descriptor for models of the `FaceGraph` concept.
     */
     typedef unspecified_type halfedge_descriptor;
 
@@ -39,7 +39,7 @@ namespace Surface_mesh_topology {
     /// clears this path.
     void clear();
 
-    /// returns `true` iff `hd` can be added at the end of this path. If `flip` is true, `hd`'s direction is reversed before checking
+    /// returns `true` iff `hd` can be added at the end of this path. If `flip` is true, the direction of `hd` is reversed before checking
     bool can_be_pushed(halfedge_descriptor hd, bool flip=false) const;
 
     /// adds `hd` at the end of this path. If `flip` is true, the opposite of `hd` is considered.
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Polygonal_schema_min_items.h b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Polygonal_schema_min_items.h
index db4bfee78f9..06fe49ab963 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Polygonal_schema_min_items.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/Polygonal_schema_min_items.h
@@ -4,7 +4,7 @@ namespace Surface_mesh_topology {
 /*!
 \ingroup PkgSurfaceMeshTopologyClasses
 
-The class `Polygonal_schema_min_items` defines a struct with a std::string as the information associated with darts, and no attribute is enabled.
+The class `Polygonal_schema_min_items` defines a struct with a `std::string` as the information associated with darts, and no attribute is enabled.
 
 \cgalModels `PolygonalSchemaItems`
 
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/draw_face_graph_with_paths.h b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/draw_face_graph_with_paths.h
index 6801173ad08..e2a13b4bf5f 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/draw_face_graph_with_paths.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/CGAL/draw_face_graph_with_paths.h
@@ -4,7 +4,7 @@ namespace CGAL {
 \ingroup PkgDrawFaceGraphWithPaths
 
 opens a new window and draws `amesh`,  either a 2D linear cell complex or a model of the FaceGraph concept, plus the paths lying on this mesh given in `apaths`.
-A call to this function is blocking, that is the program continues as soon as the user closes the window. This function requires CGAL_Qt5, and is only available if the flag CGAL_USE_BASIC_VIEWER is defined at compile time.
+A call to this function is blocking, that is the program continues as soon as the user closes the window. This function requires `CGAL_Qt5`, and is only available if the flag `CGAL_USE_BASIC_VIEWER` is defined at compile time.
 \tparam Mesh either a 2D linear cell complex or a model of the FaceGraph concept.
 \param amesh the mesh to draw.
 \param apaths the paths to draw, which should lie on `amesh`.
@@ -17,7 +17,7 @@ void draw(const Mesh& amesh,
 \ingroup PkgDrawFaceGraphWithPaths
 
 opens a new window and draws `amesh`,  either a 2D linear cell complex or a model of the FaceGraph concept, plus the paths lying on this mesh given in `apaths`.
-A call to this function is blocking, that is the program continues as soon as the user closes the window. This function requires CGAL_Qt5, and is only available if the flag CGAL_USE_BASIC_VIEWER is defined at compile time.
+A call to this function is blocking, that is the program continues as soon as the user closes the window. This function requires `CGAL_Qt5`, and is only available if the flag `CGAL_USE_BASIC_VIEWER` is defined at compile time.
 \tparam Mesh either a 2D linear cell complex or a model of the FaceGraph concept.
 \param amesh the mesh to draw.
 \param apaths the paths to draw, which should lie on `amesh`.
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchema.h b/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchema.h
index e2ddc169269..c8ba31b3905 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchema.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchema.h
@@ -48,7 +48,7 @@ public:
   /// returns true iff the facet containing `dh` is perforated.
   bool is_perforated(Dart_const_handle dh) const;
 
-  /// Shortcut for is_perforated(get_dart_labeled(s)).
+  /// Shortcut for `is_perforated(get_dart_labeled(s))`.
   bool is_perforated(const std::string & s) const;
 
   /// perforates the facet containing `dh`. Returns the number of darts of the face; 0 if the facet was already perforated.
@@ -60,6 +60,6 @@ public:
   /// fills the facet containing `dh`. Returns the number of darts of the face; 0 if the facet was already filled.
   size_type fill_facet(Dart_handle dh);
 
-  /// Shortcut for fill_facet(get_dart_labeled(s)).
+  /// Shortcut for `fill_facet(get_dart_labeled(s))`.
   size_type fill_facet(const std::string & s);
 };
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchemaItems.h b/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchemaItems.h
index ec6d956b8f1..a92d7a1af8b 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchemaItems.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/PolygonalSchemaItems.h
@@ -2,7 +2,7 @@
   \ingroup PkgSurfaceMeshTopologyConcepts
   \cgalConcept
 
-  The concept `PolygonalSchemaItems` allows to customize a PolygonalSchema  by choosing the information associated with darts, and by enabling and disabling some attributes. `%Dart_wrapper<Map>::%Dart_info`, should be a class having a public data member std::string m_label.
+  The concept `PolygonalSchemaItems` allows to customize a `PolygonalSchema` by choosing the information associated with darts, and by enabling and disabling some attributes. `%Dart_wrapper<Map>::%Dart_info`, should be a class having a public data member std::string m_label.
 
   \cgalRefines GenericMapItems
 
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/WeightFunctor.h b/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/WeightFunctor.h
index cb2fe08f63b..291b0196170 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/WeightFunctor.h
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/Concepts/WeightFunctor.h
@@ -14,7 +14,7 @@ public:
 /// @{
 
   /*!
-    %halfedge_descriptor type. A handle to `Dart` for combinatorial/generalized maps, or a halfedge descriptor for models of the `FaceGraph` concept.
+    A handle to `Dart` for combinatorial/generalized maps, or a halfedge descriptor for models of the `FaceGraph` concept.
   */
   typedef unspecified_type halfedge_descriptor;
 
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/PackageDescription.txt b/Surface_mesh_topology/doc/Surface_mesh_topology/PackageDescription.txt
index 5a2e6da0e3c..45a0fcebbea 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/PackageDescription.txt
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/PackageDescription.txt
@@ -21,7 +21,7 @@
 \cgalPkgPicture{surface-mesh-topology-logo.png}
 \cgalPkgSummaryBegin
 \cgalPkgAuthor{Guillaume Damiand, Francis Lazarus}
-\cgalPkgDesc{This package provides a toolbox for manipulating curves on a combinatorial surface from the topological viewpoint. Two main functionalities are proposed. One is the computation of shortest curves that cannot be continuously deformed to a point. This includes the computation of the so-called edge width and face width of the vertex-edge graph of a combinatorial surface. The other functionality is the homotopy test for deciding if two given curves on a combinatorial surface can be continuously deformed one into the other.}
+\cgalPkgDesc{This package provides a toolbox for manipulating curves on a combinatorial surface from the topological point of view. Two main functionalities are proposed. One is the computation of shortest curves that cannot be continuously deformed to a point. This includes the computation of the so-called edge width and face width of the vertex-edge graph of a combinatorial surface. The other functionality is the homotopy test for deciding if two given curves on a combinatorial surface can be continuously deformed one into the other.}
 \cgalPkgManuals{Chapter_Surface_Mesh_Topology,PkgSurfaceMeshTopology}
 \cgalPkgSummaryEnd
 \cgalPkgShortInfoBegin
diff --git a/Surface_mesh_topology/doc/Surface_mesh_topology/Surface_mesh_topology.txt b/Surface_mesh_topology/doc/Surface_mesh_topology/Surface_mesh_topology.txt
index 6d13664f032..b85cc68b45c 100644
--- a/Surface_mesh_topology/doc/Surface_mesh_topology/Surface_mesh_topology.txt
+++ b/Surface_mesh_topology/doc/Surface_mesh_topology/Surface_mesh_topology.txt
@@ -8,7 +8,7 @@ namespace CGAL {
 \cgalAutoToc
 \author Guillaume Damiand and Francis Lazarus
 
-This package provides a toolbox for manipulating curves on a combinatorial surface from the topological viewpoint. Two main functionalities are proposed. One is the computation of shortest curves that cannot be continuously deformed to a point. This includes the computation of the so-called edge width and face width of the vertex-edge graph of a combinatorial surface. The other functionality is the homotopy test for deciding if two given curves on a combinatorial surface can be continuously deformed one into the other.
+This package provides a toolbox for manipulating curves on a combinatorial surface from the topological point of view. Two main functionalities are proposed. One is the computation of shortest curves that cannot be continuously deformed to a point. This includes the computation of the so-called edge width and face width of the vertex-edge graph of a combinatorial surface. The other functionality is the homotopy test for deciding if two given curves on a combinatorial surface can be continuously deformed one into the other.
 
 
 \section SMTopology Introduction
@@ -25,7 +25,7 @@ A closed curve, either topological or combinatorial, that cannot be continuously
 - Given a surface mesh \f$\cal{M}\f$, compute a shortest non-contractible combinatorial  curve without the previous vertex requirement. When all the edges have the same unit length, the length of a shortest non-contractible curve is known as the <em>edge width</em> of the surface,
 - Given a surface mesh \f$\cal{M}\f$, compute a shortest non-contractible topological curve. It can be assumed that this curve does not cross the edges of \f$\cal{M}\f$ and only passes through the vertices. It follows that the curve can be described by a circular sequence of traversed faces alternating with the vertices it passes through. The length of this curve (i.e., the number of vertices it passes through) is known as the <em>face width</em> of the surface.
 
-It is important to clarify how we compare the lengths of two combinatorial curves in order to compute the shortest one. "Shortest" can be understood as "having the least amount of edges" or "having the smallest total length of its edges". In the former case, we consider that the mesh is unweighted; in the latter case, we consider that the mesh is weighted, and one must specify how the weight, or length, of each edge is calculated (see concept `WeightFunctor`). When the vertices of the mesh have Euclidean coordinates, the Eudlidean distance between two connected vertices defines a natural weight for the corresponding edge. A weight functor \link CGAL::Surface_mesh_topology::Euclidean_length_weight_functor `Euclidean_length_weight_functor`\endlink is provided for this purpose.
+It is important to clarify how we compare the lengths of two combinatorial curves in order to compute the shortest one. "Shortest" can be understood as "having the least amount of edges" or "having the smallest total length of its edges". In the former case, we consider that the mesh is unweighted; in the latter case, we consider that the mesh is weighted, and one must specify how the weight, or length, of each edge is calculated (see concept `WeightFunctor`). When the vertices of the mesh have Euclidean coordinates, the Euclidean distance between two connected vertices defines a natural weight for the corresponding edge. A weight functor \link CGAL::Surface_mesh_topology::Euclidean_length_weight_functor `Euclidean_length_weight_functor`\endlink is provided for this purpose.
 
 The algorithm to find a shortest non-contractible curve through a specified vertex is based on the paper by Cabello et al. \cgalCite{cvl-ew-12}. The time complexity is linear, though in the weighted case it is raised by a logarithmic factor, assuming that the weight computation takes constant time per edge. Computing the edge width takes quadratic time by running the first function on each vertex, and its complexity is also raised by a logarithmic factor when considering a weighted map. Computing the face width consists of constructing the radial graph of the original mesh and computing the edge width of the radial graph. It thus takes quadratic time. Computing face width on weighted maps is currently not supported.
 
diff --git a/Surface_sweep_2/include/CGAL/Surface_sweep_2/Curve_pair.h b/Surface_sweep_2/include/CGAL/Surface_sweep_2/Curve_pair.h
index 6f6ce6dfd0a..1a50dfdcecb 100644
--- a/Surface_sweep_2/include/CGAL/Surface_sweep_2/Curve_pair.h
+++ b/Surface_sweep_2/include/CGAL/Surface_sweep_2/Curve_pair.h
@@ -157,19 +157,19 @@ public:
     return (temp);
   }
 
-  bool operator==(const Self& other)
+  bool operator==(const Self& other) const
   {
     CGAL_precondition(m_container == other.m_container);
     return (m_index == other.m_index);
   }
 
-  bool operator!=(const Self& other)
+  bool operator!=(const Self& other) const
   {
     CGAL_precondition(m_container == other.m_container);
     return !(*this == other);
   }
 
-  unsigned int operator-(const Self& other)
+  unsigned int operator-(const Self& other) const
   {
     CGAL_precondition(m_container == other.m_container);
     return (m_index - other.m_index);
diff --git a/TDS_2/doc/TDS_2/Concepts/TriangulationDSFaceBase_2.h b/TDS_2/doc/TDS_2/Concepts/TriangulationDSFaceBase_2.h
index 082daba0ec3..edb509658cd 100644
--- a/TDS_2/doc/TDS_2/Concepts/TriangulationDSFaceBase_2.h
+++ b/TDS_2/doc/TDS_2/Concepts/TriangulationDSFaceBase_2.h
@@ -183,7 +183,7 @@ void * for_compact_container() const;
 /*!
 
 */
-void * & for_compact_container();
+void for_compact_container(void *p);
 
 /// @}
 
diff --git a/TDS_2/doc/TDS_2/Concepts/TriangulationDSVertexBase_2.h b/TDS_2/doc/TDS_2/Concepts/TriangulationDSVertexBase_2.h
index a677dbb722c..37f979d4717 100644
--- a/TDS_2/doc/TDS_2/Concepts/TriangulationDSVertexBase_2.h
+++ b/TDS_2/doc/TDS_2/Concepts/TriangulationDSVertexBase_2.h
@@ -118,7 +118,7 @@ void * for_compact_container() const;
 /*!
 
 */
-void * & for_compact_container();
+void for_compact_container(void* p);
 
 /// @}
 
diff --git a/TDS_2/include/CGAL/Triangulation_data_structure_2.h b/TDS_2/include/CGAL/Triangulation_data_structure_2.h
index c72cefe1a95..f9c20e15885 100644
--- a/TDS_2/include/CGAL/Triangulation_data_structure_2.h
+++ b/TDS_2/include/CGAL/Triangulation_data_structure_2.h
@@ -104,8 +104,13 @@ protected:
 public:
   Triangulation_data_structure_2();
   Triangulation_data_structure_2(const Tds &tds);
+  Triangulation_data_structure_2(Triangulation_data_structure_2&& tds)
+    noexcept(noexcept(Face_range(std::move(tds._faces))) &&
+             noexcept(Vertex_range(std::move(tds._vertices))));
+
   ~Triangulation_data_structure_2();
   Tds& operator= (const Tds &tds);
+  Tds& operator= (Tds&& tds) noexcept(noexcept(Tds(std::move(tds))));
   void swap(Tds &tds);
 
   //ACCESS FUNCTIONS
@@ -641,9 +646,6 @@ public:
 
   Triangulation_default_data_structure_2(const Geom_traits& = Geom_traits())
     : Tds() {}
-
-  Triangulation_default_data_structure_2(const Tdds &tdds)
-    : Tds(tdds) {}
 };
 
 //for backward compatibility
@@ -656,8 +658,6 @@ public:
   typedef Triangulation_data_structure_using_list_2<Vb,Fb>  Tdsul;
 
   Triangulation_data_structure_using_list_2(): Tds() {}
-  Triangulation_data_structure_using_list_2(const Tdsul &tdsul)
-    : Tds(tdsul) {}
 };
 
 
@@ -674,6 +674,17 @@ Triangulation_data_structure_2(const Tds &tds)
   copy_tds(tds);
 }
 
+template < class Vb, class Fb>
+Triangulation_data_structure_2<Vb,Fb> ::
+Triangulation_data_structure_2(Tds &&tds)
+    noexcept(noexcept(Face_range(std::move(tds._faces))) &&
+             noexcept(Vertex_range(std::move(tds._vertices))))
+  : _dimension(std::exchange(tds._dimension, -2))
+  , _faces(std::move(tds._faces))
+  , _vertices(std::move(tds._vertices))
+{
+}
+
 template < class Vb, class Fb>
 Triangulation_data_structure_2<Vb,Fb> ::
 ~Triangulation_data_structure_2()
@@ -681,7 +692,7 @@ Triangulation_data_structure_2<Vb,Fb> ::
   clear();
 }
 
-//assignement
+//copy-assignment
 template < class Vb, class Fb>
 Triangulation_data_structure_2<Vb,Fb>&
 Triangulation_data_structure_2<Vb,Fb> ::
@@ -691,6 +702,18 @@ operator= (const Tds &tds)
   return *this;
 }
 
+//move-assignment
+template < class Vb, class Fb>
+Triangulation_data_structure_2<Vb,Fb>&
+Triangulation_data_structure_2<Vb,Fb> ::
+operator= (Tds &&tds) noexcept(noexcept(Tds(std::move(tds))))
+{
+  _faces = std::move(tds._faces);
+  _vertices = std::move(tds._vertices);
+  _dimension = std::exchange(tds._dimension, -2);
+  return *this;
+}
+
 template <  class Vb, class Fb>
 void
 Triangulation_data_structure_2<Vb,Fb>::
@@ -798,7 +821,7 @@ is_edge(Vertex_handle va, Vertex_handle vb,
 {
   Face_handle fc = va->face();
   Face_handle start = fc;
-  if (fc == 0) return false;
+  if (fc == nullptr) return false;
   int inda, indb;
   do {
     inda=fc->index(va);
@@ -1031,7 +1054,9 @@ insert_dim_up(Vertex_handle w,  bool orient)
 
       for ( ; lfit != faces_list.end() ; ++lfit) {
         f = * lfit;
-        g = create_face(f); //calls copy constructor of face
+        g = create_face(f->vertex(0),f->vertex(1),f->vertex(2),
+                        f->neighbor(0),f->neighbor(1),f->neighbor(2));
+
         f->set_vertex(dim,v);
         g->set_vertex(dim,w);
         set_adjacency(f, dim, g, dim);
diff --git a/TDS_2/include/CGAL/Triangulation_ds_face_base_2.h b/TDS_2/include/CGAL/Triangulation_ds_face_base_2.h
index 7fa6d99f5aa..cbe8b8e1d49 100644
--- a/TDS_2/include/CGAL/Triangulation_ds_face_base_2.h
+++ b/TDS_2/include/CGAL/Triangulation_ds_face_base_2.h
@@ -79,7 +79,7 @@ public:
 
    // For use by Compact_container.
   void * for_compact_container() const {return N[0].for_compact_container(); }
-  void * & for_compact_container()     { return N[0].for_compact_container();}
+  void for_compact_container(void* p) { N[0].for_compact_container(p);}
 
 
   static int ccw(int i) {return Triangulation_cw_ccw_2::ccw(i);}
diff --git a/TDS_2/include/CGAL/Triangulation_ds_vertex_base_2.h b/TDS_2/include/CGAL/Triangulation_ds_vertex_base_2.h
index 1d5df47f476..ba0386f747f 100644
--- a/TDS_2/include/CGAL/Triangulation_ds_vertex_base_2.h
+++ b/TDS_2/include/CGAL/Triangulation_ds_vertex_base_2.h
@@ -49,7 +49,7 @@ public:
 
     // For use by the Compact_container.
   void *   for_compact_container() const { return _f.for_compact_container(); }
-  void * & for_compact_container()       { return _f.for_compact_container(); }
+  void for_compact_container(void* p) { _f.for_compact_container(p); }
 
 private:
   Face_handle _f;
diff --git a/TDS_2/test/TDS_2/include/CGAL/_test_cls_tds_2.h b/TDS_2/test/TDS_2/include/CGAL/_test_cls_tds_2.h
index ae2e35b13d8..619b959937e 100644
--- a/TDS_2/test/TDS_2/include/CGAL/_test_cls_tds_2.h
+++ b/TDS_2/test/TDS_2/include/CGAL/_test_cls_tds_2.h
@@ -44,6 +44,11 @@ template <class Tds>
 void
 _test_cls_tds_2( const Tds &)
 {
+  static_assert(std::is_nothrow_move_constructible<Tds>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Tds>::value,
+                "move assignment is missing");
+
   typedef typename Tds::Vertex_range      Vertex_range;
   typedef typename Tds::Face_range        Face_range;
 
@@ -129,6 +134,34 @@ _test_cls_tds_2( const Tds &)
   assert(tds3.number_of_vertices() == 4);
   assert(tds3.is_valid() );
 
+    // Test move-constructors and move-assignments
+  {
+    Tds tds7 = tds3;
+    Tds tds8{std::move(tds7)};
+    Tds tds9 = tds3;
+    Tds tds10;
+    tds10 = std::move(tds9);
+    Tds tds11 = Tds(tds3);  // construct from a temporary
+    Tds tds12 = std::move(tds11);
+
+    assert(tds7.is_valid());
+    assert(tds8.is_valid());
+    assert(tds9.is_valid());
+    assert(tds10.is_valid());
+    assert(tds11.is_valid());
+    assert(tds12.is_valid());
+    assert(tds7.dimension()==-2);
+    assert(tds8.dimension()==1);
+    assert(tds9.dimension()==-2);
+    assert(tds10.dimension()==1);
+    assert(tds11.dimension()==-2);
+    assert(tds12.dimension()==1);
+    tds11.~Tds();
+    // check tds12 is still valid after the destruction of tds11
+    assert(tds12.is_valid());
+    assert(tds12.dimension()==1);
+  }
+
   Vertex_handle w4 = tds4.insert_first();
   Vertex_handle v4_1 = tds4.insert_second();
   Vertex_handle v4_2 = tds4.insert_dim_up(w4,true);
diff --git a/TDS_3/doc/TDS_3/Concepts/TriangulationDSCellBase_3.h b/TDS_3/doc/TDS_3/Concepts/TriangulationDSCellBase_3.h
index eed775ffac6..0c7108a3d67 100644
--- a/TDS_3/doc/TDS_3/Concepts/TriangulationDSCellBase_3.h
+++ b/TDS_3/doc/TDS_3/Concepts/TriangulationDSCellBase_3.h
@@ -136,7 +136,7 @@ void * for_compact_container() const;
 /*!
 
 */
-void * & for_compact_container();
+void for_compact_container(void *p);
 
 /// @}
 
diff --git a/TDS_3/doc/TDS_3/Concepts/TriangulationDSVertexBase_3.h b/TDS_3/doc/TDS_3/Concepts/TriangulationDSVertexBase_3.h
index 14c6293b902..9435ee7e9e5 100644
--- a/TDS_3/doc/TDS_3/Concepts/TriangulationDSVertexBase_3.h
+++ b/TDS_3/doc/TDS_3/Concepts/TriangulationDSVertexBase_3.h
@@ -116,7 +116,7 @@ void * for_compact_container() const;
 /*!
 
 */
-void * & for_compact_container();
+void for_compact_container(void *);
 
 /*!
 Inputs the non-combinatorial information given by the vertex.
diff --git a/TDS_3/include/CGAL/Triangulation_data_structure_3.h b/TDS_3/include/CGAL/Triangulation_data_structure_3.h
index 6e154098cb5..52200b7a795 100644
--- a/TDS_3/include/CGAL/Triangulation_data_structure_3.h
+++ b/TDS_3/include/CGAL/Triangulation_data_structure_3.h
@@ -231,6 +231,15 @@ public:
     copy_tds(tds);
   }
 
+  Triangulation_data_structure_3(Tds && tds)
+    noexcept(noexcept(Cell_range(std::move(tds._cells))) &&
+             noexcept(Vertex_range(std::move(tds._vertices))))
+    : _dimension(std::exchange(tds._dimension, -2))
+    , _cells(std::move(tds._cells))
+    , _vertices(std::move(tds._vertices))
+  {
+  }
+
   Tds & operator= (const Tds & tds)
   {
     if (&tds != this) {
@@ -240,6 +249,17 @@ public:
     return *this;
   }
 
+  Tds & operator= (Tds && tds)
+    noexcept(noexcept(Tds(std::move(tds))))
+  {
+    _cells = std::move(tds._cells);
+    _vertices = std::move(tds._vertices);
+    _dimension = std::exchange(tds._dimension, -2);
+    return *this;
+  }
+
+  ~Triangulation_data_structure_3() = default; // for the rule-of-five
+
   size_type number_of_vertices() const { return vertices().size(); }
 
   int dimension() const {return _dimension;}
@@ -917,12 +937,6 @@ public:
         *output++ = e;
         return *this;
       }
-      Facet_it& operator=(const Facet_it& f) {
-        output = f.output;
-        filter = f.filter;
-        return *this;
-      }
-      Facet_it(const Facet_it&)=default;
     };
     Facet_it facet_it() {
       return Facet_it(output, filter);
@@ -1047,6 +1061,15 @@ public:
       }
     }
 
+    // Implement the rule-of-five, to please the diagnostic
+    // `cppcoreguidelines-special-member-functions` of clang-tidy.
+    // Instead of defaulting those special member functions, let's
+    // delete them, to prevent any misuse.
+    Vertex_extractor(const Vertex_extractor&) = delete;
+    Vertex_extractor(Vertex_extractor&&) = delete;
+    Vertex_extractor& operator=(const Vertex_extractor&) = delete;
+    Vertex_extractor& operator=(Vertex_extractor&&) = delete;
+
     ~Vertex_extractor()
     {
       for(std::size_t i=0; i < tmp_vertices.size(); ++i){
diff --git a/TDS_3/include/CGAL/Triangulation_ds_cell_base_3.h b/TDS_3/include/CGAL/Triangulation_ds_cell_base_3.h
index 23cb03cf170..ced30ffe6c1 100644
--- a/TDS_3/include/CGAL/Triangulation_ds_cell_base_3.h
+++ b/TDS_3/include/CGAL/Triangulation_ds_cell_base_3.h
@@ -180,7 +180,7 @@ public:
 
   // For use by Compact_container.
   void * for_compact_container() const { return N[0].for_compact_container(); }
-  void * & for_compact_container()     { return N[0].for_compact_container(); }
+  void for_compact_container(void* p) { N[0].for_compact_container(p); }
 
   // TDS internal data access functions.
         TDS_data& tds_data()       { return _tds_data; }
diff --git a/TDS_3/include/CGAL/Triangulation_ds_vertex_base_3.h b/TDS_3/include/CGAL/Triangulation_ds_vertex_base_3.h
index fc3067b6f02..3322157b797 100644
--- a/TDS_3/include/CGAL/Triangulation_ds_vertex_base_3.h
+++ b/TDS_3/include/CGAL/Triangulation_ds_vertex_base_3.h
@@ -59,8 +59,8 @@ public:
   // For use by the Compact_container.
   void *   for_compact_container() const
   { return _c.for_compact_container(); }
-  void * & for_compact_container()
-  { return _c.for_compact_container(); }
+  void for_compact_container(void* p)
+  { _c.for_compact_container(p); }
 
 private:
   Cell_handle _c;
diff --git a/TDS_3/test/TDS_3/CMakeLists.txt b/TDS_3/test/TDS_3/CMakeLists.txt
index b21488fe951..87f0c8a318e 100644
--- a/TDS_3/test/TDS_3/CMakeLists.txt
+++ b/TDS_3/test/TDS_3/CMakeLists.txt
@@ -9,10 +9,11 @@ if ( CGAL_FOUND )
   include_directories (BEFORE "./include")
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
   create_single_source_cgal_program( "test_triangulation_tds_3.cpp" )
   create_single_source_cgal_program( "test_io_tds3.cpp" )
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(test_triangulation_tds_3)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(test_triangulation_tds_3 PUBLIC CGAL::TBB_support)
   endif()
 else()
   message(STATUS "This program requires the CGAL library, and will not be compiled.")
diff --git a/TDS_3/test/TDS_3/include/CGAL/_test_cls_tds_3.h b/TDS_3/test/TDS_3/include/CGAL/_test_cls_tds_3.h
index 5352d97cace..1364bf8b137 100644
--- a/TDS_3/test/TDS_3/include/CGAL/_test_cls_tds_3.h
+++ b/TDS_3/test/TDS_3/include/CGAL/_test_cls_tds_3.h
@@ -26,6 +26,11 @@ template <class Tds>
 void
 _test_cls_tds_3( const Tds &)
 {
+  static_assert(std::is_nothrow_move_constructible<Tds>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Tds>::value,
+                "move assignment is missing");
+
   typedef typename Tds::Vertex_range      Vertex_range;
   typedef typename Tds::Cell_range        Cell_range;
 
@@ -115,6 +120,34 @@ _test_cls_tds_3( const Tds &)
   std::cout << "ok" << std::endl;
   assert(tds6.is_valid());
 
+  // Test move-constructors and move-assignments
+  {
+    Tds tds7 = tds5;
+    Tds tds8{std::move(tds7)};
+    Tds tds9 = tds5;
+    Tds tds10;
+    tds10 = std::move(tds9);
+    Tds tds11 = Tds(tds5);  // construct from a temporary
+    Tds tds12 = std::move(tds11);
+
+    assert(tds7.is_valid());
+    assert(tds8.is_valid());
+    assert(tds9.is_valid());
+    assert(tds10.is_valid());
+    assert(tds11.is_valid());
+    assert(tds12.is_valid());
+    assert(tds7.dimension()==-2);
+    assert(tds8.dimension()==2);
+    assert(tds9.dimension()==-2);
+    assert(tds10.dimension()==2);
+    assert(tds11.dimension()==-2);
+    assert(tds12.dimension()==2);
+    tds11.~Tds();
+    // check tds12 is still valid after the destruction of tds11
+    assert(tds12.is_valid());
+    assert(tds12.dimension()==2);
+  }
+
   std::cout << "  Insert are tested in test_triangulation_3  " << std::endl;
 
   std::cout << "  Iterator and circulator are tested in test_triangulation_3  " << std::endl;
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingCellBase_3.h b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingCellBase_3.h
new file mode 100644
index 00000000000..6a55d55b842
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingCellBase_3.h
@@ -0,0 +1,13 @@
+/*!
+\ingroup PkgTetrahedralRemeshingConcepts
+\cgalConcept
+
+\cgalRefines MeshCellBase_3
+
+Cell base concept to be used in the triangulation type given to the function `CGAL::tetrahedral_isotropic_remeshing()`.
+
+\cgalHasModel `CGAL::Tetrahedral_remeshing::Remeshing_cell_base_3`.
+
+*/
+class RemeshingCellBase_3
+{};
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingTriangulationTraits_3.h b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingTriangulationTraits_3.h
new file mode 100644
index 00000000000..8f001943705
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingTriangulationTraits_3.h
@@ -0,0 +1,135 @@
+
+/*!
+\ingroup PkgTetrahedralRemeshingConcepts
+\cgalConcept
+
+\cgalRefines TriangulationTraits_3
+
+The concept `RemeshingTriangulationTraits_3` is the first template parameter
+of the class `Remeshing_triangulation_3`. It defines the geometric objects
+(points, segments, triangles, and tetrahedra) forming the triangulation together with a few
+geometric predicates and constructions on these objects.
+
+\cgalHasModel All models of `Kernel`.
+
+\sa `CGAL::Triangulation_3`
+*/
+
+class RemeshingTriangulationTraits_3 {
+public:
+
+/// \name Types
+/// @{
+
+/*!
+A constructor object model of `ConstructCrossProductVector_3`
+*/
+typedef unspecified_type Construct_cross_product_vector_3;
+
+/*!
+A constructor object model of `ConstructVector_3`
+*/
+typedef unspecified_type Construct_vector_3;
+
+/*!
+A constructor object model of `ConstructScaledVector_3 `
+*/
+typedef unspecified_type Construct_scaled_vector_3;
+
+/*!
+A constructor object model of `ConstructSumOfVectors_3`
+*/
+typedef unspecified_type Construct_sum_of_vectors_3;
+
+/*!
+A constructor object model of `ConstructOppositeVector_3`
+*/
+typedef unspecified_type Construct_opposite_vector_3;
+
+/*!
+A constructor object model of `ComputeSquaredLength_3`
+*/
+typedef unspecified_type Compute_squared_length_3;
+
+/*!
+A constructor object model of `ConstructDividedVector_3`
+*/
+typedef unspecified_type Construct_divided_vector_3;
+
+/*!
+A constructor object model of `ConstructTranslatedPoint_3`
+*/
+typedef unspecified_type Construct_translated_point_3;
+
+/*!
+A constructor object model of `ConstructMidpoint_3`
+*/
+typedef unspecified_type Construct_midpoint_3;
+
+/*!
+A constructor obeject model of `ComputeApproximateDihedralAngle_3`
+*/
+typedef unspecified_type Compute_approximate_dihedral_angle_3;
+
+/////*!
+////A predicate object that must provide the function operator
+////
+////`Comparison_result operator()(Point_3 p, Point_3 q)`,
+////
+////which returns `EQUAL` if the two points are equal. Otherwise it must
+////return a consistent order for any two points chosen in a same line.
+////*/
+////typedef unspecified_type Compare_xyz_3;
+
+
+/// @}
+
+
+/// \name Operations
+/// The following functions give access to the predicate and construction objects:
+/// @{
+
+/*!
+*/
+Construct_cross_product_vector_3 construct_cross_product_vector_3_object();
+
+/*!
+*/
+Construct_vector_3 construct_vector_3_object();
+
+/*!
+*/
+Construct_scaled_vector_3 construct_scaled_vector_3_object();
+
+/*!
+*/
+Construct_sum_of_vectors_3 construct_sum_of_vectors_3_object();
+
+/*!
+*/
+Construct_opposite_vector_3 construct_opposite_vector_3_object();
+
+/*!
+*/
+Compute_squared_length_3 compute_squared_length_3_object();
+
+/*!
+*/
+Construct_divided_vector_3 construct_divided_vector_3_object();
+
+/*!
+*/
+Construct_translated_point_3 construct_translated_point_3_object();
+
+/*!
+*/
+Construct_midpoint_3         construct_midpoint_3_object();
+
+/*!
+*/
+Compute_approximate_dihedral_angle_3 compute_approximate_dihedral_angle_3_object();
+
+/// @}
+
+}; /* end RemeshingTriangulationTraits_3 */
+
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingVertexBase_3.h b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingVertexBase_3.h
new file mode 100644
index 00000000000..fa524edef74
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Concepts/RemeshingVertexBase_3.h
@@ -0,0 +1,13 @@
+/*!
+\ingroup PkgTetrahedralRemeshingConcepts
+\cgalConcept
+
+\cgalRefines MeshVertexBase_3
+
+Vertex base concept to be used in the triangulation type given to the function `CGAL::tetrahedral_isotropic_remeshing()`.
+
+\cgalHasModel `CGAL::Tetrahedral_remeshing::Remeshing_vertex_base_3`.
+
+*/
+class RemeshingVertexBase_3
+{};
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Doxyfile.in b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Doxyfile.in
new file mode 100644
index 00000000000..a7812ca0fd3
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Doxyfile.in
@@ -0,0 +1,28 @@
+@INCLUDE = ${CGAL_DOC_PACKAGE_DEFAULTS}
+PROJECT_NAME = "CGAL ${CGAL_DOC_VERSION} - Tetrahedral Remeshing"
+
+#custom options for this package
+EXTRACT_ALL          = false
+HIDE_UNDOC_CLASSES   = true
+WARN_IF_UNDOCUMENTED = false
+
+# macros to be used inside the code
+ALIASES += "cgalNamedParamsBegin=<dl class=\"params\"><dt>Named Parameters</dt><dd> <table class=\"params\">"
+ALIASES += "cgalNamedParamsEnd=</table> </dd> </dl>"
+ALIASES += "cgalParamBegin{1}=<tr><td class=\"paramname\">\ref Remeshing_\1 \"\1\"</td><td>"
+ALIASES += "cgalParamEnd=</td></tr>"
+
+#macros for NamedParameters.txt
+ALIASES += "cgalNPTableBegin=<dl class=\"params\"><dt></dt><dd> <table class=\"params\">"
+ALIASES += "cgalNPTableEnd=</table> </dd> </dl>"
+ALIASES += "cgalNPBegin{1}=<tr><td class=\"paramname\">\1 </td><td>"
+ALIASES += "cgalNPEnd=</td></tr>"
+
+EXAMPLE_PATH += ${CGAL_Tetrahedral_remeshing_EXAMPLE_DIR}
+
+EXCLUDE = ${CGAL_PACKAGE_INCLUDE_DIR}/CGAL/Tetrahedral_remeshing/internal
+
+#MACRO_EXPANSION        = YES
+#EXPAND_ONLY_PREDEF     = YES
+#EXPAND_AS_DEFINED      = CGAL_PMP_NP_TEMPLATE_PARAMETERS \
+#                        CGAL_PMP_NP_CLASS
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/NamedParameters.txt b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/NamedParameters.txt
new file mode 100644
index 00000000000..953042d5f33
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/NamedParameters.txt
@@ -0,0 +1,100 @@
+/*!
+\defgroup Remeshing_namedparameters Named Parameters for Tetrahedral Remeshing
+\ingroup PkgTetrahedralRemeshingRef
+
+\cgalHeading{How to use BGL Optional Named Parameters}
+
+The notion of named parameters was introduced in the BGL.
+Details can be found from: https://www.boost.org/libs/graph/doc/bgl_named_params.html.
+Named parameters enable the user to specify only those parameters which are really needed, by name,
+making the parameter ordering not required.
+See \ref BGLNamedParameters for more information on how to use them.
+
+The sequence of named parameters should start with `CGAL::parameters::`.
+The function `CGAL::parameters::all_default()` can be used to indicate
+that default values of optional named parameters are used.
+<!-- clashing tag with PMP named space -->
+
+\cgalHeading{List of Available Named Parameters}
+
+In this package, functions optional parameters are implemented as BGL optional named parameters and listed below.
+
+In the following, we assume that the following types are provided as template parameters of tetrahedral remeshing
+functions. Note that the type may be more specific for some functions.
+
+<ul>
+<li>`Triangulation` implements a `Triangulation_3` with specific vertex base and cell base.</li>
+</ul>
+
+\cgalNPTableBegin
+
+\cgalNPBegin{number_of_iterations}
+\anchor Remeshing_number_of_iterations
+the number of iterations for the full sequence of atomic operations
+(edge splits, edge collapses, edge flips, smoothing and projection to the initial surface)
+performed to reach the input target edge length while improving the quality of dihedral angles
+in the mesh.\n
+\b Type : `std::size_t` \n
+\b Default value is `1`
+\cgalNPEnd
+
+\cgalNPBegin{remesh_boundaries}
+\anchor Remeshing_remesh_boundaries
+a Boolean that states whether the boundaries should be remeshed or
+exactly preserved by the remeshing process.
+Boundaries are between the exterior and the interior,
+between two subdomains, between the areas selected or not for remeshing
+(cf \ref Remeshing_cell_is_selected_map),
+or defined by \ref Remeshing_edge_is_constrained_map
+and \ref Remeshing_facet_is_constrained_map.
+If `true`, they are remeshed. Otherwise, they cannot be modified at all by the remeshing process.\n
+\b Type : `bool` \n
+\b Default value is `true`
+\cgalNPEnd
+
+\cgalNPBegin{edge_is_constrained_map}
+\anchor Remeshing_edge_is_constrained_map
+is a property map containing information about edges of the input triangulation
+being marked as constrained or not.\n
+<b>Type:</b> a class model of `ReadWritePropertyMap` with
+`std::pair<Triangulation::%Vertex_handle, Triangulation::%Vertex_handle>` as key type and
+`bool` as value type.
+The pairs must be ordered to ensure consistency.
+During the meshing process, the set of constrained edges evolves consistently with
+edge splits and collapses, so the property map must be writable.
+It must be default constructible.
+\n
+<b>Default:</b> a default property map where no edge is constrained
+\cgalNPEnd
+
+\cgalNPBegin{facet_is_constrained_map}
+\anchor Remeshing_facet_is_constrained_map
+is a property map containing information about facets of the input triangulation
+being marked as constrained or not.\n
+<b>Type:</b> a class model of `ReadPropertyMap` with
+`Triangulation::%Facet` as key type and `bool` as value type.
+It is not updated throughout the remeshing process.
+It must be default constructible.
+\n
+<b>Default:</b> a default property map where no facet is constrained
+\cgalNPEnd
+
+\cgalNPBegin{cell_is_selected_map}
+\anchor Remeshing_cell_is_selected_map
+is a property map containing information about cells of the input triangulation
+being marked as selected or not for tetrahedral remeshing.
+Only selected cells are modified (and possibly their neighbors if surfaces are
+modified) by the remeshing process. Unselected cells will not be modified.\n
+\b Type : a class model of `ReadWritePropertyMap` with
+`Triangulation::%Cell_handle` as key type and `bool` as value type.
+During the meshing process, the set of selected cells evolves consistently with
+the atomic operations that are performed,
+so the property map must be writable.
+It must be default constructible.\n
+<b>Default:</b> a default property map where all cells of the domain
+(i.e. with a non-zero `Subdomain_index`) are selected.
+\cgalNPEnd
+
+\cgalNPTableEnd
+
+*/
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/PackageDescription.txt b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/PackageDescription.txt
new file mode 100644
index 00000000000..b0935baf35a
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/PackageDescription.txt
@@ -0,0 +1,52 @@
+// Tetrahedral Remeshing
+
+/// \defgroup PkgTetrahedralRemeshingRef Tetrahedral Remeshing Reference
+/// \defgroup PkgTetrahedralRemeshingConcepts Concepts
+/// \ingroup PkgTetrahedralRemeshingRef
+
+/// \defgroup PkgTetrahedralRemeshingClasses Classes
+/// \ingroup PkgTetrahedralRemeshingRef
+
+/*!
+\addtogroup PkgTetrahedralRemeshingRef
+
+\cgalPkgDescriptionBegin{Tetrahedral Remeshing,PkgTetrahedralRemeshing}
+\cgalPkgPicture{bimba_back_small.png}
+
+\cgalPkgSummaryBegin
+\cgalPkgAuthors{Jane Tournois, Noura Faraj}
+\cgalPkgDesc{
+The package provides a function for remeshing tetrahedral meshes,
+targetting high quality meshes with respect to dihedral angles.}
+\cgalPkgManuals{Chapter_Tetrahedral_Remeshing,PkgTetrahedralRemeshingRef}
+\cgalPkgSummaryEnd
+
+\cgalPkgShortInfoBegin
+\cgalPkgSince{5.1}
+\cgalPkgDependsOn{\ref PkgTriangulation3}
+\cgalPkgBib{faraj2016mvr}
+\cgalPkgLicense{\ref licensesGPL "GPL"}
+\cgalPkgDemo{Polyhedron demo,polyhedron_3.zip}
+\cgalPkgShortInfoEnd
+
+\cgalPkgDescriptionEnd
+
+\cgalClassifedRefPages
+
+\cgalCRPSection{Concepts}
+
+- `RemeshingTriangulationTraits_3`
+- `RemeshingVertexBase_3`
+- `RemeshingCellBase_3`
+
+\cgalCRPSection{Classes}
+
+- `CGAL::Tetrahedral_remeshing::Remeshing_vertex_base_3`
+- `CGAL::Tetrahedral_remeshing::Remeshing_cell_base_3`
+- `CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3`
+
+\cgalCRPSection{Function Templates}
+
+- `CGAL::tetrahedral_isotropic_remeshing()`
+
+*/
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Tetrahedral_remeshing.txt b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Tetrahedral_remeshing.txt
new file mode 100644
index 00000000000..bca4311f67d
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/Tetrahedral_remeshing.txt
@@ -0,0 +1,101 @@
+namespace CGAL {
+/*!
+
+\mainpage User Manual
+\anchor Chapter_Tetrahedral_Remeshing
+\anchor userchaptertetrahedralremeshing
+
+\cgalAutoToc
+\authors Jane Tournois, Noura Faraj
+
+\image html bimba_back.png
+\image latex bimba_back.png
+<BR>
+
+\section secTetRemeshing Multi-Material Isotropic Tetrahedral Remeshing
+
+This package implements an algorithm for quality tetrahedral remeshing,
+introduced by N.Faraj et al in \cgalCite{faraj2016mvr}.
+This practical iterative remeshing algorithm is designed to remesh
+multi-material tetrahedral meshes, by iteratively performing a sequence of
+elementary operations such as edge splits, edge collapses, edge flips,
+and vertex relocations following a Laplacian smoothing.
+The algorithm results in high-quality uniform isotropic meshes,
+with the desired mesh density,
+while preserving the input geometric curve and surface features.
+
+Specific remeshing rules have been designed to satisfy the following criteria.
+First, the algorithm preserves the geometric complex topology, including
+multi-material surface patches and polyline features. Polyline features
+can be defined as intersections between more than two subdomains, or listed by
+the user. Second, it has been made possible to remesh only a selection of cells,
+instead of remeshing the whole domain, while preserving or remeshing the
+interface surfaces between the preserved and the remeshed tetrahedra.
+
+All the local atomic operations that are performed by the algorithm
+preserve the input topology of the geometric complex.
+
+The tetrahedral remeshing algorithm improves the quality of dihedral angles,
+while targeting the user-defined uniform sizing field and preserving the
+topology of the feature complex, as highlighted by Figure \cgalFigureRef{Remesh_liver}.
+
+\cgalFigureBegin{Remesh_liver, tetrahedral_remeshing_before_after.png}
+Tetrahedral mesh, improved by the uniform tetrahedral remeshing algorithm.
+(Left) Before remeshing, dihedral angles were in the interval [0.7; 178.9].
+(Right) After remeshing and keeping the same density,
+dihedral angles are the interval [12,7; 157.7].
+\cgalFigureEnd
+
+Experimental evidence shows that a higher number of remeshing iterations
+leads to a mesh with a improved fidelity to the sizing criterion,
+and higher quality dihedral angles.
+
+\section secTetRemeshingAPI API
+
+The tetrahedral remeshing algorithm is implemented as a single free function
+`CGAL::tetrahedral_isotropic_remeshing()` that
+takes only two required parameters: the input triangulation, and the desired edge length,
+which drives the remeshing process.
+
+\ref BGLNamedParameters are used to deal with optional parameters.
+The page \ref Remeshing_namedparameters provides a description
+of their usage, and of all the available parameters for tuning
+the remeshing process and results.
+
+
+\section secTetRemeshingExamples Examples
+
+\subsection ssecEx1 Tetrahedral Remeshing Example
+
+The following example shows the simplest use of the tetrahedral remeshing function.
+The only required parameter is a given target edge length that drives the remeshing process
+towards a high-quality tetrahedral mesh with improved dihedral angles, and a more
+uniform mesh, with edge lengths getting closer to the input parameter value.
+
+\cgalExample{Tetrahedral_remeshing/tetrahedral_remeshing_example.cpp }
+
+
+\subsection ssecEx2 Tetrahedral Remeshing of A Selection
+
+Optional BGL named parameters offer more precise
+control on the remeshing process. In this example, a triangulation with two subdomains
+(defined by indices stored in cells) is given as input, but only one
+(defined by the `Subdomain_index` 2)
+of its subdomains is remeshed.
+
+\cgalExample{Tetrahedral_remeshing/tetrahedral_remeshing_of_one_subdomain.cpp }
+
+
+\subsection ssecEx3 Tetrahedral Remeshing With Polyline Features
+
+Optional BGL named parameters offer more precise
+control on the remeshing process. In this example, a triangulation
+with polyline features that should be preserved - though resampled -
+during the remeshing process, is given as input.
+Preserving all surfaces exactly could also be achieved by
+setting the named parameter `remesh_boundaries` to `false`.
+
+\cgalExample{Tetrahedral_remeshing/tetrahedral_remeshing_with_features.cpp }
+
+*/
+} /* namespace CGAL */
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/dependencies b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/dependencies
new file mode 100644
index 00000000000..30913764fab
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/dependencies
@@ -0,0 +1,10 @@
+Manual
+Kernel_23
+STL_Extension
+Algebraic_foundations
+Circulator
+Stream_support
+Triangulation_3
+BGL
+Mesh_3
+TDS_3
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/examples.txt b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/examples.txt
new file mode 100644
index 00000000000..e8c4a45bee1
--- /dev/null
+++ b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/examples.txt
@@ -0,0 +1,7 @@
+/*!
+
+\example Tetrahedral_remeshing/tetrahedral_remeshing_example.cpp
+\example Tetrahedral_remeshing/tetrahedral_remeshing_of_one_subdomain.cpp
+\example Tetrahedral_remeshing/tetrahedral_remeshing_with_features.cpp
+
+*/
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/bimba_back.png b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/bimba_back.png
new file mode 100644
index 00000000000..45ec300bc67
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diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/bimba_back_small.png b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/bimba_back_small.png
new file mode 100644
index 00000000000..f0f2c0912f3
Binary files /dev/null and b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/bimba_back_small.png differ
diff --git a/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/tetrahedral_remeshing_before_after.png b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/tetrahedral_remeshing_before_after.png
new file mode 100644
index 00000000000..de0380aaad4
Binary files /dev/null and b/Tetrahedral_remeshing/doc/Tetrahedral_remeshing/fig/tetrahedral_remeshing_before_after.png differ
diff --git a/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/CMakeLists.txt b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/CMakeLists.txt
new file mode 100644
index 00000000000..ecc37356c72
--- /dev/null
+++ b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/CMakeLists.txt
@@ -0,0 +1,27 @@
+# Created by the script cgal_create_CMakeLists
+# This is the CMake script for compiling a set of CGAL applications.
+
+cmake_minimum_required(VERSION 3.1...3.14)
+
+project( Tetrahedral_remeshing_Examples )
+
+# CGAL and its components
+find_package( CGAL REQUIRED )
+if ( NOT CGAL_FOUND )
+  message(STATUS "This project requires the CGAL library, and will not be compiled.")
+  return()
+endif()
+
+# Boost and its components
+find_package( Boost REQUIRED )
+if ( NOT Boost_FOUND )
+  message(STATUS "This project requires the Boost library, and will not be compiled.")
+  return()
+endif()
+
+
+# Creating entries for all C++ files with "main" routine
+# ##########################################################
+create_single_source_cgal_program( "tetrahedral_remeshing_example.cpp" )
+create_single_source_cgal_program( "tetrahedral_remeshing_with_features.cpp")
+create_single_source_cgal_program( "tetrahedral_remeshing_of_one_subdomain.cpp")
diff --git a/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_example.cpp b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_example.cpp
new file mode 100644
index 00000000000..da292fe7d0a
--- /dev/null
+++ b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_example.cpp
@@ -0,0 +1,29 @@
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+
+#include <CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h>
+#include "tetrahedral_remeshing_generate_input.h"
+
+#include <iostream>
+#include <fstream>
+#include <string>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+
+int main(int argc, char* argv[])
+{
+  const double target_edge_length = (argc > 1) ? atof(argv[1]) : 0.1;
+  const std::size_t nbv = (argc > 2) ? atoi(argv[2]) : 1000;
+
+  Remeshing_triangulation tr;
+  CGAL::Tetrahedral_remeshing::generate_input_one_subdomain(nbv, tr);
+
+  CGAL::tetrahedral_isotropic_remeshing(tr, target_edge_length);
+
+  return EXIT_SUCCESS;
+}
diff --git a/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_generate_input.h b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_generate_input.h
new file mode 100644
index 00000000000..7f020ae5c6a
--- /dev/null
+++ b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_generate_input.h
@@ -0,0 +1,191 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#include <CGAL/Random.h>
+
+#include <boost/unordered_set.hpp>
+#include <utility>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+  template<typename Tr>
+  void generate_input_two_subdomains(const std::size_t& nbv, Tr& tr)
+  {
+    CGAL::Random rng;
+
+    typedef typename Tr::Point Point;
+    typedef typename Tr::Cell_handle Cell_handle;
+
+    while (tr.number_of_vertices() < nbv)
+      tr.insert(Point(rng.get_double(-1., 1.), rng.get_double(-1., 1.), rng.get_double(-1., 1.)));
+
+    const typename Tr::Geom_traits::Plane_3
+      plane(Point(0, 0, 0), Point(0, 1, 0), Point(0, 0, 1));
+
+    for (Cell_handle c : tr.finite_cell_handles())
+    {
+      if (plane.has_on_positive_side(
+        CGAL::centroid(c->vertex(0)->point(), c->vertex(1)->point(),
+                       c->vertex(2)->point(), c->vertex(3)->point())))
+        c->set_subdomain_index(1);
+      else
+        c->set_subdomain_index(2);
+    }
+    CGAL_assertion(tr.is_valid(true));
+  }
+
+
+  template<typename Tr>
+  void generate_input_one_subdomain(const std::size_t nbv, Tr& tr)
+  {
+    CGAL::Random rng;
+
+    typedef typename Tr::Point Point;
+    std::vector<Point> pts;
+    while (pts.size() < nbv)
+    {
+      const double x = rng.get_double(-1., 1.);
+      const double y = rng.get_double(-1., 1.);
+      const double z = rng.get_double(-1., 1.);
+
+      pts.push_back(Point(x, y, z));
+    }
+    tr.insert(pts.begin(), pts.end());
+
+    for (typename Tr::Cell_handle c : tr.finite_cell_handles())
+      c->set_subdomain_index(1);
+
+    CGAL_assertion(tr.is_valid(true));
+  }
+
+  template<typename Tr>
+  void add_edge(typename Tr::Vertex_handle v1,
+    typename Tr::Vertex_handle v2,
+    const Tr& tr,
+    boost::unordered_set<std::pair<typename Tr::Vertex_handle,
+                                   typename Tr::Vertex_handle> >& constraints)
+  {
+    typename Tr::Cell_handle c;
+    int i, j;
+    if (tr.is_edge(v1, v2, c, i, j))
+      constraints.insert(std::make_pair(v1, v2));
+  }
+
+  template<typename Tr>
+  void make_constraints_from_cube_edges(
+    Tr& tr,
+    boost::unordered_set<std::pair<typename Tr::Vertex_handle,
+                                   typename Tr::Vertex_handle> >& constraints)
+  {
+    typedef typename Tr::Point Point;
+    typedef typename Tr::Vertex_handle Vertex_handle;
+    typedef typename Tr::Cell_handle Cell_handle;
+
+    const Point p0(-2., -2., -2.);
+    const Point p1(-2., -2., -2.);
+    const Point p2(2., -2., -2.);
+    const Point p3(2., -2., 2.);
+    const Point p4(-2., 2., -2.);
+    const Point p5(-2., 2., 2.);
+    const Point p6(2., 2., -2.);
+    const Point p7(2., 2., 2.);
+
+    typename Tr::Locate_type lt;
+    int li, lj;
+    Cell_handle c = tr.locate(p0, lt, li, lj);
+    Vertex_handle v0 = c->vertex(li);
+    c = tr.locate(p1, lt, li, lj);
+    Vertex_handle v1 = c->vertex(li);
+
+    c = tr.locate(p2, lt, li, lj);
+    Vertex_handle v2 = c->vertex(li);
+    c = tr.locate(p3, lt, li, lj);
+    Vertex_handle v3 = c->vertex(li);
+
+    c = tr.locate(p4, lt, li, lj);
+    Vertex_handle v4 = c->vertex(li);
+    c = tr.locate(p5, lt, li, lj);
+    Vertex_handle v5 = c->vertex(li);
+
+    c = tr.locate(p6, lt, li, lj);
+    Vertex_handle v6 = c->vertex(li);
+    c = tr.locate(p7, lt, li, lj);
+    Vertex_handle v7 = c->vertex(li);
+
+    // constrain cube edges
+    add_edge(v0, v1, tr, constraints);
+    add_edge(v1, v2, tr, constraints);
+    add_edge(v2, v3, tr, constraints);
+    add_edge(v3, v0, tr, constraints);
+
+    add_edge(v4, v5, tr, constraints);
+    add_edge(v5, v6, tr, constraints);
+    add_edge(v6, v7, tr, constraints);
+    add_edge(v7, v4, tr, constraints);
+
+    add_edge(v0, v4, tr, constraints);
+    add_edge(v1, v5, tr, constraints);
+    add_edge(v2, v6, tr, constraints);
+    add_edge(v3, v7, tr, constraints);
+  }
+
+  template<typename Tr>
+  void generate_input_cube(const std::size_t& n,
+    Tr& tr,
+    boost::unordered_set<std::pair<typename Tr::Vertex_handle,
+                                   typename Tr::Vertex_handle> >& constraints)
+  {
+    typedef typename Tr::Vertex_handle Vertex_handle;
+    typedef typename Tr::Point Point;
+    CGAL::Random rng;
+
+    // points in a sphere
+    std::vector<Point> pts;
+    while (pts.size() < n)
+      pts.push_back(Point(rng.get_double(-1., 1.), rng.get_double(-1., 1.), rng.get_double(-1., 1.)));
+    tr.insert(pts.begin(), pts.end());
+
+    // vertices of a larger cube
+    Vertex_handle v0 = tr.insert(Point(-2., -2., -2.));
+    Vertex_handle v1 = tr.insert(Point(-2., -2., 2.));
+
+    Vertex_handle v2 = tr.insert(Point(2., -2., -2.));
+    Vertex_handle v3 = tr.insert(Point(2., -2., 2.));
+
+    Vertex_handle v4 = tr.insert(Point(-2., 2., -2.));
+    Vertex_handle v5 = tr.insert(Point(-2., 2., 2.));
+
+    Vertex_handle v6 = tr.insert(Point(2., 2., -2.));
+    Vertex_handle v7 = tr.insert(Point(2., 2., 2.));
+
+    // constrain cube edges
+    add_edge(v0, v1, tr, constraints);
+    add_edge(v1, v2, tr, constraints);
+    add_edge(v2, v3, tr, constraints);
+    add_edge(v3, v0, tr, constraints);
+
+    add_edge(v4, v5, tr, constraints);
+    add_edge(v5, v6, tr, constraints);
+    add_edge(v6, v7, tr, constraints);
+    add_edge(v7, v4, tr, constraints);
+
+    add_edge(v0, v4, tr, constraints);
+    add_edge(v1, v5, tr, constraints);
+    add_edge(v2, v6, tr, constraints);
+    add_edge(v3, v7, tr, constraints);
+
+    CGAL_assertion(tr.is_valid(true));
+  }
+}
+}
\ No newline at end of file
diff --git a/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_of_one_subdomain.cpp b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_of_one_subdomain.cpp
new file mode 100644
index 00000000000..6f108c48789
--- /dev/null
+++ b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_of_one_subdomain.cpp
@@ -0,0 +1,42 @@
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+
+#include "tetrahedral_remeshing_generate_input.h"
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+
+struct Cells_of_subdomain
+{
+private:
+  const int m_subdomain;
+
+public:
+  Cells_of_subdomain(const int& subdomain)
+    : m_subdomain(subdomain)
+  {}
+
+  bool operator()(Remeshing_triangulation::Cell_handle c) const
+  {
+    return m_subdomain == c->subdomain_index();
+  }
+};
+
+int main(int argc, char* argv[])
+{
+  const double target_edge_length = (argc > 1) ? atof(argv[1]) : 0.1;
+  const std::size_t nbv = (argc > 2) ? atoi(argv[2]) : 1000;
+
+  Remeshing_triangulation tr;
+  CGAL::Tetrahedral_remeshing::generate_input_two_subdomains(nbv, tr);
+
+  CGAL::tetrahedral_isotropic_remeshing(tr, target_edge_length,
+      CGAL::parameters::cell_selector(Cells_of_subdomain(2)));
+
+  return EXIT_SUCCESS;
+}
+
diff --git a/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_with_features.cpp b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_with_features.cpp
new file mode 100644
index 00000000000..581dd0a85db
--- /dev/null
+++ b/Tetrahedral_remeshing/examples/Tetrahedral_remeshing/tetrahedral_remeshing_with_features.cpp
@@ -0,0 +1,94 @@
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+
+#include <CGAL/property_map.h>
+
+#include <boost/unordered_set.hpp>
+
+#include <iostream>
+#include <utility>
+
+#include "tetrahedral_remeshing_generate_input.h"
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+typedef Remeshing_triangulation::Point         Point;
+typedef Remeshing_triangulation::Vertex_handle Vertex_handle;
+typedef Remeshing_triangulation::Cell_handle   Cell_handle;
+typedef Remeshing_triangulation::Edge          Edge;
+
+class Constrained_edges_property_map
+{
+public:
+  typedef bool                               value_type;
+  typedef bool                               reference;
+  typedef std::pair<Vertex_handle, Vertex_handle> key_type;
+  typedef boost::read_write_property_map_tag category;
+
+private:
+  boost::unordered_set<key_type>* m_set_ptr;
+
+public:
+  Constrained_edges_property_map()
+    : m_set_ptr(NULL)
+  {}
+  Constrained_edges_property_map(boost::unordered_set<key_type>* set_)
+    : m_set_ptr(set_)
+  {}
+
+public:
+  friend void put(Constrained_edges_property_map& map,
+                  const key_type& k,
+                  const bool b)
+  {
+    CGAL_assertion(map.m_set_ptr != NULL);
+    CGAL_assertion(k.first < k.second);
+    if (b)  map.m_set_ptr->insert(k);
+    else    map.m_set_ptr->erase(k);
+  }
+
+  friend value_type get(const Constrained_edges_property_map& map,
+                              const key_type& k)
+  {
+    CGAL_assertion(map.m_set_ptr != NULL);
+    CGAL_assertion(k.first < k.second);
+    return (map.m_set_ptr->count(k) > 0);
+  }
+};
+
+void set_subdomain(Remeshing_triangulation& tr, const int index)
+{
+  for (Remeshing_triangulation::Finite_cells_iterator cit = tr.finite_cells_begin();
+       cit != tr.finite_cells_end(); ++cit)
+  {
+    cit->set_subdomain_index(index);
+  }
+}
+
+int main(int argc, char* argv[])
+{
+  const double target_edge_length = (argc > 1) ? atof(argv[1]) : 0.02;
+  const int nb_iter = (argc > 2) ? atoi(argv[2]) : 1;
+  const int nbv = (argc > 3) ? atoi(argv[3]) : 500;
+
+  Remeshing_triangulation t3;
+  boost::unordered_set<std::pair<Vertex_handle, Vertex_handle> > constraints;
+
+  CGAL::Tetrahedral_remeshing::generate_input_cube(nbv, t3, constraints);
+
+  make_constraints_from_cube_edges(t3, constraints);
+
+  CGAL_assertion(t3.is_valid());
+
+  CGAL::tetrahedral_isotropic_remeshing(t3, target_edge_length,
+    CGAL::parameters::edge_is_constrained_map(
+      Constrained_edges_property_map(&constraints))
+    .number_of_iterations(nb_iter));
+
+  return EXIT_SUCCESS;
+}
+
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_cell_base_3.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_cell_base_3.h
new file mode 100644
index 00000000000..e64f67c41f2
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_cell_base_3.h
@@ -0,0 +1,65 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_TET_ADAPTIVE_REMESHING_CELL_BASE_3_H
+#define CGAL_TET_ADAPTIVE_REMESHING_CELL_BASE_3_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Mesh_cell_base_3.h>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+struct Fake_MD_C
+{
+  typedef int Subdomain_index;
+  typedef int Surface_patch_index;
+  typedef int Index;
+};
+}
+
+/*!
+\ingroup PkgTetrahedralRemeshingClasses
+
+The class `Remeshing_cell_base_3` is a model of the concept `MeshCellBase_3`.
+It is designed to serve as cell base class for the 3D triangulation
+used in the tetrahedral remeshing process.
+
+\tparam Gt is the geometric traits class.
+It has to be a model of the concept `RemeshingTriangulationTraits_3`.
+
+\tparam Cb is a cell base class from which `Remeshing_cell_base_3` derives.
+It must be a model of the `TriangulationCellBase_3` concept.
+It has the default value `Triangulation_cell_base_3<Gt>`.
+
+\cgalModels `MeshCellBase_3`
+
+*/
+#ifndef DOXYGEN_RUNNING
+template<typename Gt,
+         typename Cb = CGAL::Triangulation_cell_base_3<Gt> >
+using Remeshing_cell_base_3
+  = CGAL::Mesh_cell_base_3<Gt, internal::Fake_MD_C, Cb>;
+#else
+template<typename Gt,
+         typename Cb = CGAL::Triangulation_cell_base_3<Gt> >
+class Remeshing_cell_base_3;
+#endif
+
+}//end namespace Tetrahedral_remeshing
+}//end namespace CGAL
+
+#endif //CGAL_TET_ADAPTIVE_REMESHING_CELL_BASE_3_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h
new file mode 100644
index 00000000000..1a25ab1aace
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h
@@ -0,0 +1,77 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_TETRAHEDRAL_REMESHING_TRIANGULATION_H
+#define CGAL_TETRAHEDRAL_REMESHING_TRIANGULATION_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Triangulation_data_structure_3.h>
+#include <CGAL/Triangulation_3.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_cell_base_3.h>
+#include <CGAL/Tetrahedral_remeshing/Remeshing_vertex_base_3.h>
+
+#include <CGAL/Kernel_traits.h>
+#include <CGAL/Cartesian_converter.h>
+#include <CGAL/tags.h>
+
+#include <boost/static_assert.hpp>
+#include <boost/type_traits/is_same.hpp>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+/*!
+\ingroup PkgTetrahedralRemeshingClasses
+
+The class `Remeshing_triangulation_3`
+is a class template which provides a valid triangulation type
+that can be used as the 3D triangulation input for
+the tetrahedral remeshing process.
+
+\tparam Gt is the geometric traits class.
+It has to be a model of the concept `RemeshingTriangulationTraits_3`.
+
+\tparam Concurrency_tag enables sequential versus parallel implementation of the
+triangulation data structure.
+Possible values are `Sequential_tag` (the default), `Parallel_tag`,
+and `Parallel_if_available_tag`.
+
+\tparam Vb is a model of `RemeshingVertexBase_3`. It has the default value ` Remeshing_vertex_base_3<Gt>`.
+\tparam Cb is a model of `RemeshingCellBase_3`. It has the default value ` Remeshing_cell_base_3<Gt>`.
+
+*/
+template<typename Gt,
+         typename Concurrency_tag = CGAL::Sequential_tag,
+         typename Vb = Remeshing_vertex_base_3<Gt>,
+         typename Cb = Remeshing_cell_base_3<Gt>
+>
+class Remeshing_triangulation_3
+  : public CGAL::Triangulation_3<Gt, CGAL::Triangulation_data_structure_3<Vb,Cb> >
+{
+public:
+  typedef Vb Remeshing_Vb;
+  typedef Cb Remeshing_Cb;
+
+  typedef CGAL::Triangulation_data_structure_3<
+            Remeshing_Vb, Remeshing_Cb, Concurrency_tag>  Tds;
+  typedef CGAL::Triangulation_3<Gt, Tds>                  Base;
+
+  using Base::Base;
+};
+
+}//end namespace Tetrahedral_remeshing
+}//end namespace CGAL
+
+#endif // CGAL_TETRAHEDRAL_REMESHING_TRIANGULATION_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_vertex_base_3.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_vertex_base_3.h
new file mode 100644
index 00000000000..2d056e8e244
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Remeshing_vertex_base_3.h
@@ -0,0 +1,67 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_TET_ADAPTIVE_REMESHING_VERTEX_BASE_3_H
+#define CGAL_TET_ADAPTIVE_REMESHING_VERTEX_BASE_3_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Mesh_vertex_base_3.h>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+
+struct Fake_MD_V
+{
+  typedef int Subdomain_index;
+  typedef int Surface_patch_index;
+  typedef int Index;
+};
+
+} // internal
+
+/*!
+\ingroup PkgTetrahedralRemeshingClasses
+
+The class `Remeshing_vertex_base_3` is a model of the concept `MeshVertexBase_3`.
+It is designed to serve as vertex base class for the 3D triangulation
+used in the tetrahedral remeshing process.
+
+\tparam Gt is the geometric traits class.
+It has to be a model of the concept `RemeshingTriangulationTraits_3`.
+
+\tparam Vb is a vertex base class from which `Remeshing_vertex_base_3` derives.
+It must be a model of the `TriangulationVertexBase_3` concept.
+It has the default value `Triangulation_vertex_base_3<Gt>`.
+
+\cgalModels `MeshVertexBase_3`
+*/
+#ifndef DOXYGEN_RUNNING
+template<typename GT,
+         typename Vb = CGAL::Triangulation_vertex_base_3<GT> >
+using Remeshing_vertex_base_3
+  = CGAL::Mesh_vertex_base_3<GT, internal::Fake_MD_V, Vb>;
+#else
+template<typename GT,
+         typename Vb = CGAL::Triangulation_vertex_base_3<GT> >
+class Remeshing_vertex_base_3;
+#endif
+
+}//end namespace Tetrahedral_remeshing
+
+}//end namespace CGAL
+
+#endif //CGAL_TET_ADAPTIVE_REMESHING_VERTEX_BASE_3_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Sizing_field.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Sizing_field.h
new file mode 100644
index 00000000000..53448be56a8
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Sizing_field.h
@@ -0,0 +1,37 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_SIZING_FIELD_H
+#define CGAL_SIZING_FIELD_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+namespace CGAL
+{
+/*!
+* Sizing field virtual class
+*/
+template <class Kernel>
+class Sizing_field
+{
+public:
+  typedef Kernel                      K;
+  typedef typename Kernel::FT         FT;
+  typedef typename Kernel::Point_3    Point_3;
+
+public:
+  virtual FT operator()(const Point_3& p) const = 0;
+};
+
+}//end namespace CGAL
+
+#endif //CGAL_SIZING_FIELD_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Uniform_sizing_field.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Uniform_sizing_field.h
new file mode 100644
index 00000000000..59c7264f502
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/Uniform_sizing_field.h
@@ -0,0 +1,45 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_UNIFORM_SIZING_FIELD_H
+#define CGAL_UNIFORM_SIZING_FIELD_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Tetrahedral_remeshing/Sizing_field.h>
+
+namespace CGAL
+{
+template <class Kernel>
+class Uniform_sizing_field : Sizing_field<Kernel>
+{
+private:
+  typedef Sizing_field<Kernel>        Base;
+public:
+  typedef typename Base::FT         FT;
+  typedef typename Base::Point_3    Point_3;
+
+  Uniform_sizing_field(const FT& size)
+    : m_size(size)
+  {}
+
+  FT operator()(const Point_3&) const
+  {
+    return m_size;
+  }
+private:
+  FT m_size;
+};
+
+}//end namespace CGAL
+
+#endif //CGAL_UNIFORM_SIZING_FIELD_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/FMLS.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/FMLS.h
new file mode 100644
index 00000000000..07f6e3e3286
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/FMLS.h
@@ -0,0 +1,815 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_TETRAHEDRAL_REMESHING_FMLS_H
+#define CGAL_TETRAHEDRAL_REMESHING_FMLS_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+// -------------------------------------------
+// FMLS
+// A Fast Moving Least Square operator for 3D
+// points sets.
+// -------------------------------------------
+
+#include <CGAL/number_utils.h>
+#include <CGAL/Point_3.h>
+#include <CGAL/Vector_3.h>
+
+#include <cmath>
+#include <vector>
+#include <unordered_set>
+
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+
+#include <boost/functional/hash.hpp>
+
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+// --------------------------------------------------------------
+//  MLS Projection
+// --------------------------------------------------------------
+
+inline double wendland(double x, double h)
+{
+  x = CGAL::abs(x);
+  if (x < h)
+    return CGAL::square(CGAL::square(1 - x / h)) * (4 * x / h + 1);
+  else
+    return 0.0;
+}
+
+//inline void setPNSample(std::vector<float>& p,
+//                        const std::size_t& i,
+//                        const float x, const float y, const float z,
+//                        const float nx, const float ny, const float nz)
+//{
+//  p[6 * i] = x;
+//  p[6 * i + 1] = y;
+//  p[6 * i + 2] = z;
+//  p[6 * i + 3] = nx;
+//  p[6 * i + 4] = ny;
+//  p[6 * i + 5] = nz;
+//}
+
+template<typename Gt>
+inline CGAL::Vector_3<Gt> projectOn(const CGAL::Vector_3<Gt>& x,
+                                    const CGAL::Vector_3<Gt>& N,
+                                    const CGAL::Vector_3<Gt>& P)
+{
+  typename Gt::Compute_scalar_product_3 scalar_product
+    = Gt().compute_scalar_product_3_object();
+
+  typename Gt::FT w = scalar_product((x - P), N);
+  return x - (N * w);
+}
+
+template<typename Gt>
+inline typename Gt::FT length(const CGAL::Vector_3<Gt>& v)
+{
+  return CGAL::approximate_sqrt(v.squared_length());
+}
+
+template<typename Gt>
+inline typename Gt::FT distance(const CGAL::Vector_3<Gt>& v1,
+                                const CGAL::Vector_3<Gt>& v2)
+{
+  CGAL::Vector_3<Gt> diff(v1.x() - v2.x(),
+                          v1.y() - v2.y(),
+                          v1.z() - v2.z());
+  return length(diff);
+}
+
+template<typename Gt>
+inline void weightedPointCombination(const CGAL::Vector_3<Gt>& x,
+                                     const CGAL::Vector_3<Gt>& pi,
+                                     const CGAL::Vector_3<Gt>& ni,
+                                     double sigma_s, bool bilateral, double sigma_r,
+                                     bool hermite,
+                                     CGAL::Vector_3<Gt>& c, CGAL::Vector_3<Gt>& nc, double& sumW)
+{
+  double w = wendland(distance(x, pi), sigma_s);
+  if (bilateral)
+    w *= wendland(length(x - projectOn(x, ni, pi)), sigma_r);
+  if (hermite)
+    c += w * projectOn(x, ni, pi);
+  else
+    c += w * pi;
+  nc += w * ni;
+  sumW += w;
+}
+
+template<typename Gt>
+class FMLS
+{
+  typedef typename Gt::Vector_3 Vector_3;
+  typedef typename Gt::FT       FT;
+
+public:
+  // FMLS provide MLS projection and filtering from a point set.
+  // The underlying data structure is a simple list of float in the PN format
+  // A PN object is a list of 6xfloat32 chunk :
+  // x0,y0,z0,nx0,ny0,nz0,x1,y1,z1,nx1,ny1,nz1,...
+  // with {xi,yi,zi} the position and {nxi,nyi,nzi} the normal vector of the
+  // i-th point sample. A PN can be read from and write to file directly
+  // (identity serialization) and is handled as a simple float32 pointer.
+  //
+  // Use the 'fast*' methods. Brute force methods are inserted only for comparison.
+  //
+  // Memory policy: a FMLS class manages itself al its belonging objects.
+  // Therefore, PN and filtered PN lists are the property of this class, and should
+  // be copied if modified outside the class.
+  FMLS()
+  {
+    PNSize = 0;
+    PNScale = 1.0f;
+    MLSRadius = 0.1f;
+    bilateralRange = 0.05f;
+    bilateral = false;
+    hermite = false;
+    numIter = 1;
+  }
+
+  // --------------------------------------------------------------
+  //  Main Interface
+  // --------------------------------------------------------------
+
+//  std::vector<double> createPN(std::size_t size)
+//  {
+//    return std::vector<double>(size * SURFEL_SIZE);
+//  }
+
+  void setPN(const std::vector<double>& newPN,
+             const std::size_t newPNSize,
+             const double& pointSpacing)
+  {
+    freeCPUMemory();
+    PN = newPN;
+    PNSize = newPNSize;
+    computePNScale();
+    MLSRadius = 3 * pointSpacing / PNScale;
+    grid.clear();
+    grid.init(PN, PNSize, MLSRadius * PNScale);
+  }
+
+  // Compute, according to the current point sampling stored in FMLS, the MLS projection
+  // of p and store the resulting position in q and normal in n.
+  void fastProjectionCPU(const Vector_3& p, Vector_3& q, Vector_3& n) const
+  {
+    double sigma_s = PNScale * MLSRadius;
+    double sigma_r = bilateralRange;
+
+    const Vector_3 g = (p - Vector_3(grid.getMinMax()[0], grid.getMinMax()[1], grid.getMinMax()[2])) / sigma_s;
+
+    std::array<std::size_t, 3> gxyz;
+    for (int j = 0; j < 3; ++j)
+    {
+      if (g[j] < 0.)
+        gxyz[j] = 0;
+      if (g[j] >= grid.getRes()[j])
+        gxyz[j] = grid.getRes()[j] - 1;
+      else
+        gxyz[j] = static_cast<std::size_t>(std::floor(g[j]));
+    }
+
+    std::array<std::size_t, 3> minIt;
+    std::array<std::size_t, 3> maxIt;
+    for (std::size_t j = 0; j < 3; ++j)
+    {
+      if (gxyz[j] == 0)
+        minIt[j] = 0;
+      else
+        minIt[j] = gxyz[j] - 1;
+      if (gxyz[j] == grid.getRes()[j] - 1)
+        maxIt[j] = (grid.getRes()[j] - 1);
+      else
+        maxIt[j] = gxyz[j] + 1;
+    }
+    Vector_3 c = CGAL::NULL_VECTOR;
+    double sumW = 0.f;
+    std::array<std::size_t, 3> it;
+    for (it[0] = minIt[0]; it[0] <= maxIt[0]; it[0]++)
+      for (it[1] = minIt[1]; it[1] <= maxIt[1]; it[1]++)
+        for (it[2] = minIt[2]; it[2] <= maxIt[2]; it[2]++) {
+          std::size_t gridIndex = grid.getLUTElement(it[0], it[1], it[2]);
+          if (gridIndex == 2 * PNSize)
+            continue;
+          std::size_t neigh = grid.getCellIndicesSize(it[0], it[1], it[2]);
+          for (std::size_t j = 0; j < neigh; j++) {
+            std::size_t k = grid.getIndicesElement(it[0], it[1], it[2], j);
+            Vector_3 pk(PN[6 * k], PN[6 * k + 1], PN[6 * k + 2]);
+            Vector_3 nk(PN[6 * k + 3], PN[6 * k + 4], PN[6 * k + 5]);
+            weightedPointCombination(p, pk, nk, sigma_s, bilateral, sigma_r, hermite, c, n, sumW);
+          }
+        }
+    if (sumW == 0.f) {
+      n = Vector_3(1.f, 0.f, 0.f);
+      q = p;
+    }
+    else {
+      c /= sumW;
+      normalize(n, Gt());
+      q = projectOn(p, n, c);
+    }
+  }
+
+//  // Compute the MLS projection of the list of point stored in pv and store the resulting
+//  // positions and normal in qv. qv must be preallocated to stroe 6*pvSize float32.
+//  // The strid indicates the offsets in qv (the defautl value of 3 means that the qv
+//  // is compact: pv={x0,y0,z0,x1,y1,z1...}. If pv contains also normals for instance,
+//  // the stride should be set to 6.
+//  void fastProjectionCPU(const std::vector<float>& pv,
+//                         const std::size_t pvSize,
+//                         std::vector<float>& qv,
+//                         std::size_t stride = 3) const
+//  {
+//    for (std::size_t i = 0; i < pvSize; i++)
+//    {
+//      Vector_3 p(pv[stride * i], pv[stride * i + 1], pv[stride * i + 2]);
+//      Vector_3 q, n;
+//      for (unsigned int j = 0; j < numIter; j++)
+//      {
+//        q = CGAL::NULL_VECTOR;
+//        n = CGAL::NULL_VECTOR;
+//        fastProjectionCPU(p, q, n);
+//        p = q;
+//      }
+//      setPNSample(qv, i, q[0], q[1], q[2], n[0], n[1], n[2]);
+//    }
+//  }
+
+//  // Brute force version. O(PNSize) complexity. For comparison only.
+//  void projectionCPU(const Vector_3& x, Vector_3& q, Vector_3& n)
+//  {
+//    float sigma_s = MLSRadius * PNScale;
+//    float sigma_r = bilateralRange;
+//    Vector_3 p(x);
+//    for (unsigned int k = 0; k < numIter; k++) {
+//      Vector_3 c = CGAL::NULL_VECTOR;
+//      n = CGAL::NULL_VECTOR;
+//      float sumW = 0.f;
+//      for (unsigned int j = 0; j < PNSize; j++) {
+//        Vector_3 pj(PN[6 * j], PN[6 * j + 1], PN[6 * j + 2]);
+//        Vector_3 nj(PN[6 * j + 3], PN[6 * j + 4], PN[6 * j + 5]);
+//        weightedPointCombination(p, pj, nj, sigma_s, bilateral, sigma_r, hermite, c, n, sumW);
+//      }
+//      c /= sumW;
+//      n.normalize();
+//      q = projectOn(p, n, c);
+//      p = q;
+//    }
+//  }
+//
+//  // Brute force version. O(pvSize*PNSize) complexity. For comparison only.
+//  void projectionCPU(const std::vector<float>& pv,
+//                     unsigned int pvSize,
+//                     std::vector<float>& qv,
+//                     unsigned int stride = 3)
+//  {
+//    for (int i = 0; i < int(pvSize); i++) {
+//      Vector_3 p(pv[stride * i], pv[stride * i + 1], pv[stride * i + 2]);
+//      Vector_3 q, n;
+//      for (unsigned int j = 0; j < numIter; j++) {
+//        q = CGAL::NULL_VECTOR;
+//        n = CGAL::NULL_VECTOR;
+//        projectionCPU(p, q, n);
+//        p = q;
+//      }
+//      setPNSample(qv, i, q[0], q[1], q[2], n[0], n[1], n[2]);
+//    }
+//  }
+
+  // --------------------------------------------------------------
+  //  Accessors
+  // --------------------------------------------------------------
+
+  // Number of elements of the PN. One elemnt is a 6-float32 chunk.
+  inline std::size_t getPNSize() const { return PNSize; }
+  inline std::vector<double>& getPN() { return PN; }
+  inline const std::vector<double>& getPN() const { return PN; }
+
+  // Min/Max corners of PN's bounding volume
+  inline const double* getMinMax() const { return grid.getMinMax(); }
+  // Radius of the bounding sphere of the PN
+  inline double getPNScale() const { return PNScale; }
+  // Normalized MLS support size
+  inline double getMLSRadius() const { return MLSRadius; }
+  inline void setMLSRadius(double s) { MLSRadius = s; grid.clear(); grid.init(PN, PNSize, MLSRadius * PNScale); }
+  // Bilateral weighting for feature preservation (inspired by [Jones 2003]).
+  inline bool isBilateral() const { return bilateral; }
+  inline void toggleBilateral(bool b) { bilateral = b; }
+  // Bilateral support size for the range weight
+  inline double getBilateralRange() const { return bilateralRange; }
+  inline void setBilateralRange(double r) { bilateralRange = r; }
+  // Hermite interpolation [Alexa 2009]
+  inline bool isHermite() const { return hermite; }
+  inline void toggleHermite(bool b) { hermite = b; }
+  // Fix number of iterations of the MLS projection
+  inline unsigned int getNumOfIter() const { return numIter; }
+  inline void setNumOfIter(unsigned int i) { numIter = i; }
+
+  // --------------------------------------------------------------
+  //  Misc.
+  // --------------------------------------------------------------
+
+  // Size of a point sample in bytes (6xfloat32: 3 for position and normal
+  static const unsigned int SURFEL_SIZE = 24;
+
+private:
+
+  void computePNScale()
+  {
+    Vector_3 c = CGAL::NULL_VECTOR;
+    for (std::size_t i = 0; i < PNSize; i++)
+      c += Vector_3(PN[6 * i], PN[6 * i + 1], PN[6 * i + 2]);
+    c /= (double)PNSize;
+    PNScale = 0.;
+    for (std::size_t i = 0; i < PNSize; i++) {
+      double r = distance(c, Vector_3(PN[6 * i], PN[6 * i + 1], PN[6 * i + 2]));
+      if (r > PNScale)
+        PNScale = r;
+    }
+  }
+
+  // --------------------------------------------------------------
+  //  3D Grid Structure
+  // --------------------------------------------------------------
+  // --------------------------------------------------------------
+  //  Grid data structure for fast r-ball neighborhood query
+  // --------------------------------------------------------------
+
+  class Grid
+  {
+  public:
+    Grid()
+      : minMax()
+      , cellSize(1.f)
+      , res()
+      , LUT()
+      , indices()
+    {}
+    ~Grid()
+    {
+      clear();
+    }
+
+    void init(const std::vector<double>& PN, std::size_t PNSize, double sigma_s)
+    {
+      cellSize = sigma_s;
+      for (std::size_t i = 0; i < 3; i++) {
+        minMax[i] = PN[i];
+        minMax[3 + i] = PN[i];
+      }
+      for (std::size_t i = 0; i < PNSize; i++)
+        for (std::size_t j = 0; j < 3; j++) {
+          if (PN[6 * i + j] < minMax[j])
+            minMax[j] = PN[6 * i + j];
+          if (PN[6 * i + j] > minMax[3 + j])
+            minMax[3 + j] = PN[6 * i + j];
+        }
+      for (std::size_t i = 0; i < 3; i++) {
+        minMax[i] -= 0.001f;
+        minMax[3 + i] += 0.001f;
+      }
+      for (std::size_t i = 0; i < 3; i++)
+        res[i] = (std::size_t)ceil((minMax[3 + i] - minMax[i]) / cellSize);
+      std::size_t LUTSize = res[0] * res[1] * res[2];
+      LUT.resize(LUTSize);
+      LUT.assign(LUTSize, 0);
+
+      std::size_t nonEmptyCells = 0;
+      Vector_3 gMin(minMax[0], minMax[1], minMax[2]);
+      Vector_3 gMax(minMax[3], minMax[4], minMax[5]);
+      for (std::size_t i = 0; i < PNSize; i++) {
+        std::size_t index = getLUTIndex(Vector_3(PN[6 * i], PN[6 * i + 1], PN[6 * i + 2]));
+        if (LUT[index] == 0)
+          nonEmptyCells++;
+        LUT[index]++;
+      }
+      std::size_t indicesSize = PNSize + nonEmptyCells;
+      indices.reserve(indicesSize);
+      indices.assign(indicesSize, 0);
+
+      std::size_t cpt = 0;
+      for (std::size_t i = 0; i < res[0]; i++)
+        for (std::size_t j = 0; j < res[1]; j++)
+          for (std::size_t k = 0; k < res[2]; k++) {
+            std::size_t index = getLUTIndex(i, j, k);
+            if (LUT[index] != 0) {
+              indices[cpt] = LUT[index];
+              LUT[index] = cpt;
+              cpt += indices[cpt] + 1;
+              indices[cpt - 1] = 0; // local iterator for subsequent filling
+            }
+            else
+              LUT[index] = 2 * PNSize;
+          }
+      for (std::size_t i = 0; i < PNSize; i++) {
+        Vector_3 p = Vector_3(PN[6 * i], PN[6 * i + 1], PN[6 * i + 2]);
+        std::size_t indicesIndex = getLUTElement(p);
+        std::size_t totalCount = indices[indicesIndex];
+        std::size_t countIndex = indicesIndex + totalCount;
+        std::size_t currentCount = indices[countIndex];
+        if (currentCount < indices[indicesIndex])
+          indices[countIndex]++;
+        std::size_t pIndex = indicesIndex + 1 + currentCount;
+        indices[pIndex] = i;
+      }
+    }
+
+    void clear()
+    {
+      cellSize = 1.f;
+    }
+
+    // Accessors
+
+    inline const std::array<double, 6> getMinMax() const { return minMax; }
+    inline const std::array<std::size_t, 3> getRes() const { return res; }
+    inline double getCellSize() const { return cellSize; }
+    inline std::vector<std::size_t>& getLUT() { return LUT; }
+    inline const std::vector<std::size_t>& getLUT() const { return LUT; }
+    inline std::size_t getLUTIndex(const std::size_t i,
+                                    const std::size_t j,
+                                    const std::size_t k) const
+    {
+      return k * res[0] * res[1] + j * res[0] + i;
+    }
+    inline std::size_t getLUTElement(const std::size_t i,
+                                      const std::size_t j,
+                                      const std::size_t k) const
+    {
+      return LUT[getLUTIndex(i, j, k)];
+    }
+    std::size_t getLUTIndex(const Vector_3& x) const
+    {
+      const Vector_3 vp = (x - Vector_3(minMax[0], minMax[1], minMax[2])) / cellSize;
+      std::array<std::size_t, 3> p;
+      for (int j = 0; j < 3; j++)
+      {
+        if (vp[j] < 0)
+          p[j] = 0;
+        if (vp[j] >= res[j])
+          p[j] = res[j] - 1;
+        else
+          p[j] = static_cast<std::size_t>(std::floor(vp[j]));
+      }
+      std::size_t index = p[2] * res[0] * res[1]
+                        + p[1] * res[0]
+                        + p[0];
+      return index;
+    }
+    inline std::size_t getLUTElement(const Vector_3& x) const {
+      return LUT[getLUTIndex(x)];
+    }
+    inline std::vector<std::size_t>& getIndices() { return indices; }
+    inline const std::vector<std::size_t>& getIndices() const { return indices; }
+    inline std::size_t getCellIndicesSize(std::size_t i,
+                                           std::size_t j,
+                                           std::size_t k) const {
+      return indices[getLUTElement(i, j, k)];
+    }
+    inline std::size_t getIndicesElement(std::size_t i,
+                                          std::size_t j,
+                                          std::size_t k,
+                                          std::size_t e) const {
+      return indices[getLUTElement(i, j, k) + 1 + e];
+    }
+
+  private:
+    std::array<double, 6> minMax;
+    double cellSize;
+    std::array<std::size_t, 3> res;
+    std::vector<std::size_t> LUT; // 3D Index Look-Up Table
+    std::vector<std::size_t> indices; // 3D Grid data
+  };
+
+
+  // --------------------------------------------------------------
+  //  Memory Managment
+  // --------------------------------------------------------------
+
+  void freeCPUMemory()
+  {
+    PN.clear();
+    PNSize = 0;
+  }
+
+  // --------------------------------------------------------------
+  //  CPU Data
+  // --------------------------------------------------------------
+
+  std::vector<double> PN;
+  std::size_t PNSize;
+  double PNScale; // size of the bounding sphere radius
+  double MLSRadius;
+  double bilateralRange;
+  bool bilateral;
+  bool hermite;
+  unsigned int numIter;
+  Grid grid;
+};
+
+template<typename Subdomain__FMLS,
+         typename Subdomain__FMLS_indices,
+         typename VerticesNormalsMap,
+         typename VerticesSurfaceIndices,
+         typename C3t3>
+void createMLSSurfaces(Subdomain__FMLS& subdomain_FMLS,
+                       Subdomain__FMLS_indices& subdomain_FMLS_indices,
+                       const VerticesNormalsMap& vertices_normals,
+                       const VerticesSurfaceIndices& vertices_surface_indices,
+                       const C3t3& c3t3,
+                       const int upsample = 2) // can be 0, 1 or 2
+{
+  typedef typename C3t3::Surface_patch_index Surface_index;
+  typedef typename C3t3::Triangulation       Tr;
+  typedef typename Tr::Edge                  Edge;
+  typedef typename Tr::Vertex_handle         Vertex_handle;
+  typedef typename Tr::Geom_traits           Gt;
+  typedef typename Gt::Point_3               Point_3;
+  typedef typename Gt::Vector_3              Vector_3;
+
+  typedef typename VerticesSurfaceIndices::mapped_type    VertexSurfaces;
+  typedef typename VerticesSurfaceIndices::const_iterator VerticesSurfaceIterator;
+
+  const Tr& tr = c3t3.triangulation();
+
+  //createAreaWeightedUpSampledMLSSurfaces(0);
+  //return ;
+  subdomain_FMLS.clear();
+  subdomain_FMLS_indices.clear();
+
+  typedef boost::unordered_map<Surface_index, std::size_t> SurfaceIndexMap;
+
+  SurfaceIndexMap current_subdomain_FMLS_indices;
+  SurfaceIndexMap subdomain_sample_numbers;
+
+  //Count the number of vertices for each boundary surface (i.e. one per label)
+  for (const Vertex_handle vit : tr.finite_vertex_handles())
+  {
+    VerticesSurfaceIterator sit = vertices_surface_indices.find(vit);
+    if (sit == vertices_surface_indices.end())
+      continue;
+
+    const VertexSurfaces& v_surface_indices = vertices_surface_indices.at(vit);
+    CGAL_assertion(vit->in_dimension() <= 2);
+
+    for(const Surface_index& si : v_surface_indices)
+    {
+      subdomain_sample_numbers[si]++;
+    }
+  }
+
+  if (upsample > 0)
+  {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+    std::cout << "Up sampling MLS " << upsample << std::endl;
+#endif
+    for (typename C3t3::Facets_in_complex_iterator
+      fit = c3t3.facets_in_complex_begin();
+      fit != c3t3.facets_in_complex_end(); ++fit)
+    {
+      const Surface_index surf_i = c3t3.surface_patch_index(*fit);
+      if (upsample == 1)
+        subdomain_sample_numbers[surf_i] ++;
+      else if (upsample == 2)
+        subdomain_sample_numbers[surf_i] += 4;
+    }
+  }
+
+  std::vector< std::vector<double> > pns;
+
+  std::size_t count = 0;
+  //Memory allocation for the point plus normals of the point samples
+  for (typename SurfaceIndexMap::iterator it = subdomain_sample_numbers.begin();
+       it != subdomain_sample_numbers.end(); ++it)
+  {
+    current_subdomain_FMLS_indices[it->first] = count;
+    pns.push_back(std::vector<double>(it->second * 6, 0.));
+    count++;
+  }
+
+  std::vector<std::size_t> current_v_count(count, 0);
+  std::vector<double> point_spacing(count, 0.);
+  std::vector<int> point_spacing_count(count, 0);
+
+  //Allocation of the PN
+  for (Vertex_handle vit : tr.finite_vertex_handles())
+  {
+    VerticesSurfaceIterator sit = vertices_surface_indices.find(vit);
+    if (sit == vertices_surface_indices.end())
+      continue;
+
+    const VertexSurfaces& v_surface_indices = vertices_surface_indices.at(vit);
+    CGAL_assertion(vit->in_dimension() <= 2);
+
+    for (const Surface_index& surf_i : v_surface_indices)
+    {
+      const std::size_t& fmls_id = current_subdomain_FMLS_indices[surf_i];
+
+      const Point_3& p = point(vit->point());
+
+      pns[fmls_id][6 * current_v_count[fmls_id]] = p.x();
+      pns[fmls_id][6 * current_v_count[fmls_id] + 1] = p.y();
+      pns[fmls_id][6 * current_v_count[fmls_id] + 2] = p.z();
+
+      const Vector_3& normal = vertices_normals.at(vit).at(surf_i);
+
+      pns[fmls_id][6 * current_v_count[fmls_id] + 3] = normal.x();
+      pns[fmls_id][6 * current_v_count[fmls_id] + 4] = normal.y();
+      pns[fmls_id][6 * current_v_count[fmls_id] + 5] = normal.z();
+
+      current_v_count[fmls_id]++;
+    }
+  }
+
+  typedef std::pair<Vertex_handle, Vertex_handle> Edge_vv;
+  if (upsample == 0)
+  {
+    std::unordered_set<Edge_vv, boost::hash<Edge_vv> > edgeMap;
+
+    for (typename C3t3::Facets_in_complex_iterator
+         fit = c3t3.facets_in_complex_begin();
+         fit != c3t3.facets_in_complex_end(); ++fit)
+    {
+      for (int i = 0; i < 2; i++)
+      {
+        for (int j = i + 1; j < 3; j++)
+        {
+          Edge edge(fit->first, indices(fit->second,i), indices(fit->second,j));
+
+          Vertex_handle vh0 = edge.first->vertex(edge.second);
+          Vertex_handle vh1 = edge.first->vertex(edge.third);
+          Edge_vv e = make_vertex_pair(vh0, vh1);
+          if ( vertices_surface_indices.find(vh0) != vertices_surface_indices.end()
+               && vertices_surface_indices.find(vh1) != vertices_surface_indices.end()
+               && edgeMap.find(e) == edgeMap.end())
+          {
+            edgeMap.insert(e);
+
+            const Surface_index surf_i = c3t3.surface_patch_index(*fit);
+            const std::size_t fmls_id = current_subdomain_FMLS_indices[surf_i];
+
+            point_spacing[fmls_id] += CGAL::approximate_sqrt(
+                CGAL::squared_distance(point(vh0->point()), point(vh1->point())));
+            point_spacing_count[fmls_id] ++;
+          }
+        }
+      }
+    }
+  }
+
+  if (upsample > 0)
+  {
+    for (typename C3t3::Facets_in_complex_iterator
+         fit = c3t3.facets_in_complex_begin();
+         fit != c3t3.facets_in_complex_end(); ++fit)
+    {
+      const Surface_index surf_i = c3t3.surface_patch_index(*fit);
+
+      const std::size_t fmls_id = current_subdomain_FMLS_indices[surf_i];
+
+      Vertex_handle vhs[3] = { fit->first->vertex(indices(fit->second, 0)),
+                               fit->first->vertex(indices(fit->second, 1)),
+                               fit->first->vertex(indices(fit->second, 2)) };
+      Vector_3 points[3] = { Vector_3(CGAL::ORIGIN, point(vhs[0]->point())),
+                             Vector_3(CGAL::ORIGIN, point(vhs[1]->point())),
+                             Vector_3(CGAL::ORIGIN, point(vhs[2]->point())) };
+      Vector_3 normals[3] = { vertices_normals.at(vhs[0]).at(surf_i),
+                              vertices_normals.at(vhs[1]).at(surf_i),
+                              vertices_normals.at(vhs[2]).at(surf_i) };
+
+      std::vector<Vector_3> points_to_add;
+      std::vector<Vector_3> n_points_to_add;
+
+      //Add the barycenter of the facet
+      Vector_3 barycenter = (points[0] + points[1] + points[2]) / 3.;
+      Vector_3 n_barycenter = (normals[0] + normals[1] + normals[2]);
+
+      n_barycenter = n_barycenter / CGAL::approximate_sqrt((n_barycenter * n_barycenter));
+
+      points_to_add.push_back(barycenter);
+      n_points_to_add.push_back(n_barycenter);
+
+      if (upsample == 1)
+      {
+        for (int i = 0; i < 3; i++)
+        {
+          Vector_3 space_1 = barycenter - points[i];
+
+          point_spacing[fmls_id] += CGAL::approximate_sqrt(space_1 * space_1);
+          point_spacing_count[fmls_id] ++;
+        }
+      }
+      else if (upsample == 2)
+      {
+        for (int i = 0; i < 3; i++)
+        {
+          int i1 = (i + 1) % 3;
+          int i2 = (i + 2) % 3;
+
+          Vector_3 p = (barycenter + points[i1] + points[i2]) / 3.;
+          Vector_3 n = (n_barycenter + normals[i1] + normals[i2]);
+
+          n = n / CGAL::sqrt(n * n);
+
+          points_to_add.push_back(p);
+          n_points_to_add.push_back(n);
+
+          Vector_3 space_1 = p - barycenter;
+          Vector_3 space_2 = p - points[i1];
+          Vector_3 space_3 = p - points[i2];
+
+          point_spacing[fmls_id] += CGAL::approximate_sqrt(space_1 * space_1);
+          point_spacing[fmls_id] += CGAL::approximate_sqrt(space_2 * space_2);
+          point_spacing[fmls_id] += CGAL::approximate_sqrt(space_3 * space_3);
+
+          point_spacing_count[fmls_id] += 3;
+        }
+      }
+      for (std::size_t i = 0; i < points_to_add.size(); i++)
+      {
+        Vector_3& point = points_to_add[i];
+
+        pns[fmls_id][6 * current_v_count[fmls_id]] = point.x();
+        pns[fmls_id][6 * current_v_count[fmls_id] + 1] = point.y();
+        pns[fmls_id][6 * current_v_count[fmls_id] + 2] = point.z();
+
+        Vector_3& normal = n_points_to_add[i];
+
+        pns[fmls_id][6 * current_v_count[fmls_id] + 3] = normal.x();
+        pns[fmls_id][6 * current_v_count[fmls_id] + 4] = normal.y();
+        pns[fmls_id][6 * current_v_count[fmls_id] + 5] = normal.z();
+
+        current_v_count[fmls_id]++;
+      }
+    }
+  }
+
+
+  std::size_t nb_of_mls_to_create = 0;
+  double average_point_spacing = 0;
+
+  //Cretaing the actual MLS surfaces
+  for (typename SurfaceIndexMap::iterator it = current_subdomain_FMLS_indices.begin();
+       it != current_subdomain_FMLS_indices.end(); ++it)
+  {
+    if (current_v_count[it->second] > 3)
+    {
+      nb_of_mls_to_create++;
+
+      double current_point_spacing = point_spacing[it->second] / point_spacing_count[it->second];
+      point_spacing[it->second] = current_point_spacing;
+
+      average_point_spacing += current_point_spacing;
+    }
+  }
+
+  average_point_spacing = average_point_spacing / nb_of_mls_to_create;
+
+  subdomain_FMLS.resize(nb_of_mls_to_create, FMLS<Gt>());
+
+  count = 0;
+  //Creating the actual MLS surfaces
+  for (typename SurfaceIndexMap::iterator it = current_subdomain_FMLS_indices.begin();
+       it != current_subdomain_FMLS_indices.end(); ++it)
+  {
+    if (current_v_count[it->second] > 3)
+    {
+      const double current_point_spacing = point_spacing[it->second];
+
+      //subdomain_FMLS[count].toggleHermite(true);
+      subdomain_FMLS[count].setPN(pns[it->second],
+                                  current_v_count[it->second],
+                                  current_point_spacing);
+      //  subdomain_FMLS[count].toggleHermite(true);
+      subdomain_FMLS_indices[it->first] = count;
+
+      count++;
+    }
+    else {
+      std::cout << "Problem of number for MLS : " << current_v_count[it->second] << std::endl;
+    }
+  }
+}
+
+} // internal
+} // Tetrahedral_remeshing
+} // CGAL
+
+#endif //CGAL_TETRAHEDRAL_REMESHING_FMLS_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h
new file mode 100644
index 00000000000..4e163f07372
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h
@@ -0,0 +1,1310 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_INTERNAL_COLLAPSE_SHORT_EDGES_H
+#define CGAL_INTERNAL_COLLAPSE_SHORT_EDGES_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <boost/bimap.hpp>
+#include <boost/bimap/set_of.hpp>
+#include <boost/bimap/multiset_of.hpp>
+#include <boost/array.hpp>
+#include <boost/unordered_set.hpp>
+#include <boost/container/small_vector.hpp>
+
+#include <vector>
+#include <algorithm>
+#include <unordered_map>
+#include <utility>
+#include <unordered_set>
+
+#include <CGAL/Mesh_3/tet_soup_to_c3t3.h>
+#include <CGAL/utility.h>
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+enum Edge_type     { FEATURE, BOUNDARY, INSIDE, MIXTE,
+                     NO_COLLAPSE, INVALID, IMAGINARY, MIXTE_IMAGINARY, HULL_EDGE };
+enum Collapse_type { TO_MIDPOINT, TO_V0, TO_V1, IMPOSSIBLE };
+enum Result_type   { VALID,
+                     V_PROBLEM, C_PROBLEM, E_PROBLEM,
+                     TOPOLOGICAL_PROBLEM, ORIENTATION_PROBLEM, SHARED_NEIGHBOR_PROBLEM };
+
+template<typename C3t3>
+class CollapseTriangulation
+{
+  typedef typename C3t3::Triangulation                        Tr;
+  typedef typename C3t3::Edge                                 Edge;
+  typedef typename C3t3::Cell_handle                          Cell_handle;
+  typedef typename C3t3::Vertex_handle                        Vertex_handle;
+  typedef typename C3t3::Subdomain_index                      Subdomain_index;
+  typedef typename C3t3::Triangulation::Point                 Point_3;
+  typedef typename C3t3::Triangulation::Geom_traits::Vector_3 Vector_3;
+
+public:
+  CollapseTriangulation(C3t3& c3t3,
+                        const Edge& e,
+                        Collapse_type _collapse_type)
+    : collapse_type(_collapse_type)
+    , v0_init(e.first->vertex(e.second))
+    , v1_init(e.first->vertex(e.third))
+  {
+    typedef std::array<int, 3> Facet; // 3 = id
+    typedef std::array<int, 5> Tet_with_ref; // first 4 = id, fifth = reference
+
+    std::unordered_set<Cell_handle> cells_to_insert;
+    c3t3.triangulation().finite_incident_cells(v0_init,
+      std::inserter(cells_to_insert, cells_to_insert.end()));
+    c3t3.triangulation().finite_incident_cells(v1_init,
+      std::inserter(cells_to_insert, cells_to_insert.end()));
+
+    make_cells_set_manifold(c3t3, cells_to_insert);
+
+    std::unordered_set<Vertex_handle> vertices_to_insert;
+    for (Cell_handle ch : cells_to_insert)
+    {
+      for(int i = 0; i < 4; ++i)
+        vertices_to_insert.insert(ch->vertex(i));
+    }
+
+    CGAL_assertion(vertices_to_insert.end()
+      != std::find(vertices_to_insert.begin(), vertices_to_insert.end(), v1_init));
+    CGAL_assertion(vertices_to_insert.end()
+      != std::find(vertices_to_insert.begin(), vertices_to_insert.end(), v0_init));
+
+    std::unordered_map<Vertex_handle, int> v2i;/*vertex of main tr - vertex of collapse tr*/
+
+    //To add the vertices only once
+    std::vector<Point_3> points;
+    int index = 0;
+    for (Vertex_handle vh : vertices_to_insert)
+    {
+      if (v2i.find(vh) == v2i.end())
+      {
+        points.push_back(vh->point());
+        v2i.insert(std::make_pair(vh, index++));
+      }
+    }
+
+    std::vector<Tet_with_ref> finite_cells;
+    for (Cell_handle ch : cells_to_insert)
+    {
+      Tet_with_ref t = { { v2i.at(ch->vertex(0)),
+                           v2i.at(ch->vertex(1)),
+                           v2i.at(ch->vertex(2)),
+                           v2i.at(ch->vertex(3)),
+                           ch->subdomain_index() } };
+      finite_cells.push_back(t);
+    }
+
+    // finished
+    std::vector<Vertex_handle> new_vertices;
+    std::map<Facet, int> border_facets;
+     if (CGAL::build_triangulation<Tr, false>(triangulation,
+                                              points, finite_cells, border_facets,
+                                              new_vertices, false/*verbose*/))
+    {
+      CGAL_assertion(triangulation.tds().is_valid());
+      CGAL_assertion(triangulation.infinite_vertex() == new_vertices[0]);
+
+      // update()
+      vh0 = new_vertices[v2i.at(v0_init) + 1];
+      vh1 = new_vertices[v2i.at(v1_init) + 1];
+
+      Cell_handle ch;
+      int i0, i1;
+      not_an_edge = true;
+      CGAL_assertion(triangulation.tds().is_vertex(vh0));
+      CGAL_assertion(triangulation.tds().is_vertex(vh1));
+      if (triangulation.is_edge(vh0, vh1, ch, i0, i1))
+      {
+        edge = Edge(ch, i0, i1);
+        not_an_edge = false;
+      }
+    }
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+    else
+      std::cout << "Warning : CollapseTriangulation is not valid!" << std::endl;
+#endif
+  }
+
+  void make_cells_set_manifold(const C3t3& c3t3,
+                               std::unordered_set<Cell_handle>& cells)
+  {
+    typedef Vertex_handle Vh;
+    typedef std::array<Vh, 3> FV;
+    typedef std::pair<Vh, Vh> EV;
+
+    boost::unordered_map<FV, int> facets;
+    for (Cell_handle c : cells)
+    {
+      for (int i = 0; i < 4; ++i)
+      {
+        const FV fvi = make_vertex_array(c->vertex((i + 1) % 4),
+                                         c->vertex((i + 2) % 4),
+                                         c->vertex((i + 3) % 4));
+        typename boost::unordered_map<FV, int>::iterator fit = facets.find(fvi);
+        if(fit == facets.end())
+          facets.insert(std::make_pair(fvi, 1));
+        else
+          fit->second++;
+      }
+    }
+
+    boost::unordered_map<EV, int> edges;
+    for (const std::pair<FV, int>& fvv : facets)
+    {
+      if(fvv.second != 1)
+        continue;
+
+      for (int i = 0; i < 3; ++i)
+      {
+        const EV evi = make_vertex_pair(fvv.first[i], fvv.first[(i + 1) % 3]);
+        typename boost::unordered_map<EV, int>::iterator eit = edges.find(evi);
+        if (eit == edges.end())
+          edges.insert(std::make_pair(evi, 1));
+        else
+          eit->second++;
+      }
+    }
+
+    for (const std::pair<EV, int>& evv : edges)
+    {
+      if (evv.second != 2)
+      {
+        c3t3.triangulation().finite_incident_cells(evv.first.first,
+          std::inserter(cells, cells.begin()));
+        c3t3.triangulation().finite_incident_cells(evv.first.second,
+          std::inserter(cells, cells.begin()));
+      }
+    }
+  }
+
+  Result_type collapse()
+  {
+    if (not_an_edge)
+    {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+      std::cout << "CollapseTriangulation::Not an edge..." << std::endl;
+#endif
+      return E_PROBLEM;
+    }
+    else
+    {
+      Vector_3 v0_new_pos = vec(vh0->point());
+
+      if (collapse_type == TO_MIDPOINT){
+        v0_new_pos = v0_new_pos + 0.5 * Vector_3(point(vh0->point()), point(vh1->point()));
+      }
+      else if (collapse_type == TO_V1){
+        v0_new_pos = vec(point(vh1->point()));
+      }
+
+      boost::unordered_set<Cell_handle> invalid_cells;
+
+      typedef typename Tr::Cell_circulator Cell_circulator;
+      Cell_circulator circ = triangulation.incident_cells(edge);
+      Cell_circulator done = circ;
+
+      std::vector<Cell_handle> cells_to_remove;
+
+      //Update the vertex before removing it
+      std::vector<Cell_handle> find_incident;
+      triangulation.incident_cells(vh0, std::back_inserter(find_incident));
+
+      std::vector<Cell_handle> cells_to_update;
+      triangulation.incident_cells(vh1, std::back_inserter(cells_to_update));
+
+      do
+      {
+        int v0_id = circ->index(vh0);
+        int v1_id = circ->index(vh1);
+
+        Cell_handle n0_ch = circ->neighbor(v0_id);
+        Cell_handle n1_ch = circ->neighbor(v1_id);
+
+        int ch_id_in_n0 = n0_ch->index(circ);
+        int ch_id_in_n1 = n1_ch->index(circ);
+
+        if (n0_ch->has_neighbor(n1_ch))
+          return SHARED_NEIGHBOR_PROBLEM;
+
+        //Update neighbors before removing cell
+        n0_ch->set_neighbor(ch_id_in_n0, n1_ch);
+        n1_ch->set_neighbor(ch_id_in_n1, n0_ch);
+
+        Subdomain_index si_n0 = n0_ch->subdomain_index();
+        Subdomain_index si_n1 = n1_ch->subdomain_index();
+        Subdomain_index si = circ->subdomain_index();
+
+        if (si_n0 != si && si_n1 != si)
+          return TOPOLOGICAL_PROBLEM;
+
+        if ( triangulation.is_infinite(n0_ch->vertex(ch_id_in_n0))
+             && triangulation.is_infinite(n1_ch->vertex(ch_id_in_n1)))
+          return TOPOLOGICAL_PROBLEM;
+
+        if ( triangulation.is_infinite(n0_ch)
+             && triangulation.is_infinite(n1_ch)
+             && !triangulation.is_infinite(circ))
+          return TOPOLOGICAL_PROBLEM;
+
+        cells_to_remove.push_back(circ);
+
+        invalid_cells.insert(circ);
+
+      } while (++circ != done);
+
+
+      vh0->set_point(Point_3(v0_new_pos.x(), v0_new_pos.y(), v0_new_pos.z()));
+      vh1->set_point(Point_3(v0_new_pos.x(), v0_new_pos.y(), v0_new_pos.z()));
+
+      Vertex_handle infinite_vertex = triangulation.infinite_vertex();
+
+      bool v0_updated = false;
+      for (const Cell_handle ch : find_incident)
+      {
+        if (invalid_cells.find(ch) == invalid_cells.end()) //valid cell
+        {
+          if (triangulation.is_infinite(ch))
+            infinite_vertex->set_cell(ch);
+          else {
+            vh0->set_cell(ch);
+            v0_updated = true;
+          }
+        }
+      }
+
+      //Update the vertex before removing it
+      for (Cell_handle ch : cells_to_update)
+      {
+        if (invalid_cells.find(ch) == invalid_cells.end()) //valid cell
+        {
+          ch->set_vertex(ch->index(vh1), vh0);
+
+          if (triangulation.is_infinite(ch))
+            infinite_vertex->set_cell(ch);
+          else {
+            if (!v0_updated) {
+              vh0->set_cell(ch);
+              v0_updated = true;
+            }
+          }
+        }
+      }
+
+      if (!v0_updated){
+        std::cout << "CollapseTriangulation::PB i cell not valid!!!" << std::endl;
+        return V_PROBLEM;
+      }
+      triangulation.tds().delete_vertex(vh1);
+
+      //Removing cells
+      for (Cell_handle ch : cells_to_remove){
+        triangulation.tds().delete_cell(ch);
+      }
+
+      for (Cell_handle cit : triangulation.finite_cell_handles())
+      {
+        if (!is_well_oriented(triangulation, cit))
+          return ORIENTATION_PROBLEM;
+        if (!triangulation.tds().is_valid(cit, true))
+          return C_PROBLEM;
+      }
+
+      for (Vertex_handle vit : triangulation.finite_vertex_handles())
+      {
+        if (!triangulation.tds().is_valid(vit, true))
+          return V_PROBLEM;
+      }
+
+      //int si_nb_vh0 = nb_incident_subdomains(vh0, c3t3);
+      //int si_nb_vh1 = nb_incident_subdomains(vh1, c3t3);
+      //int vertices_subdomain_nb_vh0 = std::max(si_nb_vh0, si_nb_vh1);
+      //bool is_on_hull_vh0 = is_on_convex_hull(vh0, c3t3) || is_on_convex_hull(vh1, c3t3);
+
+      //if( is_valid_for_domains() )
+      return VALID;
+
+      // return TOPOLOGICAL_PROBLEM;
+    }
+  }
+
+protected:
+  Tr triangulation;
+
+  const Collapse_type collapse_type;
+
+  const Vertex_handle v0_init;
+  const Vertex_handle v1_init;
+
+  Vertex_handle vh0;
+  Vertex_handle vh1;
+
+  Edge edge;
+
+  bool not_an_edge;
+};
+
+
+
+template<typename C3t3, typename CellSelector>
+Collapse_type get_collapse_type(const typename C3t3::Edge& edge,
+                                const C3t3& c3t3,
+                                CellSelector cell_selector)
+{
+  bool update_v0 = false;
+  bool update_v1 = false;
+  get_edge_info(edge, update_v0, update_v1, c3t3, cell_selector);
+
+  if (update_v0 && update_v1) return TO_MIDPOINT;
+  else if (update_v0)         return TO_V1;
+  else if (update_v1)         return TO_V0;
+  else                        return IMPOSSIBLE;
+}
+
+//template<typename C3t3>
+//Edge_type get_edge_type(const typename C3t3::Edge& edge,
+//                        const C3t3& c3t3)
+//{
+//  typedef typename C3t3::Vertex_handle Vertex_handle;
+//  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+//  typedef typename C3t3::Subdomain_index Subdomain_index;
+
+//  const Vertex_handle & v0 = edge.first->vertex(edge.second);
+//  const Vertex_handle & v1 = edge.first->vertex(edge.third);
+
+//  const int dim0 = c3t3.in_dimension(v0);
+//  const int dim1 = c3t3.in_dimension(v1);
+
+//  const bool is_v0_on_hull = is_on_convex_hull(v0, c3t3);
+//  const bool is_v1_on_hull = is_on_convex_hull(v1, c3t3);
+
+//  if (c3t3.is_in_complex(edge))
+//    return FEATURE;
+
+//  else if (dim0 == 3 && dim1 == 3)
+//    return INSIDE;
+
+//  else if (dim0 == 2 && dim1 == 2)
+//  {
+//    Cell_circulator circ = c3t3.triangulation().incident_cells(edge);
+//    Cell_circulator done = circ;
+
+//    std::vector<Subdomain_index> indices;
+//    do
+//    {
+//      Subdomain_index current_si = circ->subdomain_index();
+
+//      if (std::find(indices.begin(), indices.end(), current_si) == indices.end()) {
+//        indices.push_back(current_si);
+//      }
+
+//      Subdomain_index si_n0 = circ->neighbor(circ->index(v0))->subdomain_index();
+//      Subdomain_index si_n1 = circ->neighbor(circ->index(v1))->subdomain_index();
+//      if (si_n0 == si_n1 && si_n0 != current_si)
+//        return NO_COLLAPSE;
+
+//    } while (++circ != done);
+
+//    const std::size_t nb_si_v0 = nb_incident_subdomains(v0, c3t3);
+//    const std::size_t nb_si_v1 = nb_incident_subdomains(v1, c3t3);
+
+//    if (indices.size() >= (std::min)(nb_si_v0, nb_si_v1)) {
+//      return BOUNDARY;
+//    }
+//  }
+
+//  //std::cerr << "ERROR : get_edge_type did not return anything valid!" << std::endl;
+//  return NO_COLLAPSE;
+//}
+
+template<typename C3t3>
+bool is_valid_collapse(const typename C3t3::Edge& edge,
+                       const C3t3& c3t3)
+{
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+  typedef typename C3t3::Cell_handle   Cell_handle;
+  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+
+  Cell_circulator circ = c3t3.triangulation().incident_cells(edge);
+  Cell_circulator done = circ;
+  do
+  {
+    int v0_id = circ->index(v0);
+    int v1_id = circ->index(v1);
+
+    Cell_handle n0_ch = circ->neighbor(v0_id);
+    Cell_handle n1_ch = circ->neighbor(v1_id);
+
+    if (n0_ch->has_vertex(v0)
+        || n1_ch->has_vertex(v1)
+        || n0_ch->has_neighbor(n1_ch))
+    {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+      if (c3t3.is_in_complex(edge))
+        ++nb_invalid_collapse_short;
+#endif
+      return false;
+    }
+  }
+  while (++circ != done);
+
+  return true;
+}
+
+template<typename C3t3>
+bool is_valid_collapse(const typename C3t3::Edge& edge,
+                       const Collapse_type& collapse_type,
+                       const typename C3t3::Triangulation::Point& new_pos,
+                       const C3t3& c3t3)
+{
+  typedef typename C3t3::Vertex_handle        Vertex_handle;
+  typedef typename C3t3::Cell_handle          Cell_handle;
+  typedef typename C3t3::Triangulation::Point Point;
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+  const bool in_cx = c3t3.is_in_complex(edge);
+  if (in_cx)
+  {
+    if (collapse_type == TO_MIDPOINT)
+      nb_test_midpoint++;
+    else if (collapse_type == TO_V1)
+      nb_test_v1++;
+    else
+      nb_test_v0++;
+  }
+#endif
+
+  if (collapse_type == TO_V1 || collapse_type == TO_MIDPOINT)
+  {
+    std::vector<Cell_handle> cells_to_check;
+    c3t3.triangulation().finite_incident_cells(v0,
+        std::back_inserter(cells_to_check));
+
+    for (const Cell_handle ch : cells_to_check)
+    {
+      if (!ch->has_vertex(v1))
+      {
+        //check orientation
+        boost::array<Point, 4> pts = { ch->vertex(0)->point(),
+                                       ch->vertex(1)->point(),
+                                       ch->vertex(2)->point(),
+                                       ch->vertex(3)->point()};
+        pts[ch->index(v0)] = new_pos;
+        if (CGAL::orientation(point(pts[0]), point(pts[1]), point(pts[2]), point(pts[3]))
+            != CGAL::POSITIVE)
+        {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+          if (in_cx)
+          {
+            if (collapse_type == TO_MIDPOINT)
+              nb_orientation_midpoint++;
+            else
+              nb_orientation_v1++;
+          }
+#endif
+          return false;
+        }
+      }
+    }
+  }
+  if (collapse_type == TO_V0 || collapse_type == TO_MIDPOINT)
+  {
+    std::vector<Cell_handle> cells_to_check;
+    c3t3.triangulation().finite_incident_cells(v1,
+        std::back_inserter(cells_to_check));
+
+    for (const Cell_handle ch : cells_to_check)
+    {
+      if (!ch->has_vertex(v0))
+      {
+        //check orientation
+        boost::array<Point, 4> pts = { ch->vertex(0)->point(),
+                                       ch->vertex(1)->point(),
+                                       ch->vertex(2)->point(),
+                                       ch->vertex(3)->point() };
+        pts[ch->index(v1)] = new_pos;
+        if (CGAL::orientation(point(pts[0]), point(pts[1]), point(pts[2]), point(pts[3]))
+            != CGAL::POSITIVE)
+        {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+          if (in_cx)
+          {
+            if (collapse_type == TO_MIDPOINT)
+              nb_orientation_midpoint++;
+            else
+              nb_orientation_v0++;
+          }
+#endif
+          return false;
+        }
+      }
+    }
+  }
+
+  return is_valid_collapse(edge, c3t3);
+}
+
+template<typename Facet, typename Vh>
+bool facet_has_edge(const Facet& f, const Vh v0, const Vh v1)
+{
+  std::array<std::array<int, 2>, 3> edges = {{ {{1,2}}, {{2,3}}, {{3,1}} }};
+
+  for (int i = 0; i < 3; ++i)
+  {
+    const std::array<int, 2>& ei = edges[i];
+    if ( f.first->vertex((f.second + ei[0]) % 4) == v0
+      && f.first->vertex((f.second + ei[1]) % 4) == v1)
+      return true;
+    if ( f.first->vertex((f.second + ei[0]) % 4) == v1
+      && f.first->vertex((f.second + ei[1]) % 4) == v0)
+      return true;
+  }
+  return false;
+}
+
+template<typename C3t3, typename CellSelector>
+bool collapse_preserves_surface_star(const typename C3t3::Edge& edge,
+                                     const C3t3& c3t3,
+                                     const typename C3t3::Triangulation::Point& new_pos,
+                                     const CellSelector& cell_selector)
+{
+  typedef typename C3t3::Triangulation       Tr;
+  typedef typename C3t3::Vertex_handle       Vertex_handle;
+  typedef typename C3t3::Facet               Facet;
+  typedef typename Tr::Geom_traits::Vector_3 Vector_3;
+  typedef typename Tr::Geom_traits::Point_3  Point_3;
+
+  const Tr& tr = c3t3.triangulation();
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+  if (c3t3.in_dimension(v0) != 2 || c3t3.in_dimension(v1) != 2)
+    return true;//other cases should not be treated here
+
+  typename Tr::Geom_traits gt = c3t3.triangulation().geom_traits();
+  typename Tr::Geom_traits::Construct_opposite_vector_3
+    opp = gt.construct_opposite_vector_3_object();
+  typename Tr::Geom_traits::Compute_scalar_product_3
+    product = gt.compute_scalar_product_3_object();
+  typename Tr::Geom_traits::Construct_normal_3
+    normal = gt.construct_normal_3_object();
+
+  boost::unordered_set<Facet> facets;
+  tr.finite_incident_facets(v0, std::inserter(facets, facets.end()));
+  tr.finite_incident_facets(v1, std::inserter(facets, facets.end()));
+
+// note : checking a 2nd ring of facets does not change the result
+//  boost::unordered_set<Facet> ring2;
+//  for (const Facet& f : facets)
+//  {
+//    for (int i = 1; i < 4; ++i)
+//    {
+//      Vertex_handle vi = f.first->vertex((f.second + i) % 4);
+//      tr.finite_incident_facets(vi, std::inserter(ring2, ring2.end()));
+//    }
+//  }
+//  facets.insert(ring2.begin(), ring2.end());
+
+  Vector_3 reference_normal = CGAL::NULL_VECTOR;
+  //Point_3 reference_c;
+  for (const Facet& f : facets)
+  {
+    if (!is_boundary(c3t3, f, cell_selector))
+      continue;
+    if (facet_has_edge(f, v0, v1))
+      continue; //this facet will collapse if collapse happens
+
+    std::array<Point_3, 3> pts = {{ point(f.first->vertex((f.second + 1) % 4)->point()),
+                                    point(f.first->vertex((f.second + 2) % 4)->point()),
+                                    point(f.first->vertex((f.second + 3) % 4)->point()) }};
+    if(f.second % 2 == 0)
+      std::swap(pts[0], pts[1]);
+
+    Vector_3 n_before_collapse = normal(pts[0], pts[1], pts[2]);
+
+    const Facet& mf = tr.mirror_facet(f);
+    bool do_opp = false;
+    if (  c3t3.triangulation().is_infinite(mf.first)
+      ||  c3t3.subdomain_index(mf.first) < c3t3.subdomain_index(f.first))
+    {
+      n_before_collapse = opp(n_before_collapse);
+      do_opp = true;
+    }
+
+    if (reference_normal == CGAL::NULL_VECTOR)
+    {
+      //reference_c = CGAL::centroid(pts[0], pts[1], pts[2]);
+      reference_normal = n_before_collapse;
+    }
+
+    // check after move
+    for (int i = 0; i < 3; ++i)
+    {
+      const Vertex_handle vi = f.first->vertex((f.second + i + 1) % 4);
+      if (vi == v0 || vi == v1)
+      {
+        if (f.second % 2 == 0)
+        {
+          if(i == 0)      pts[1] = point(new_pos);
+          else if(i == 1) pts[0] = point(new_pos);
+          else            pts[2] = point(new_pos);
+        }
+        else
+          pts[i] = point(new_pos);
+        break;
+      }
+    }
+
+    Vector_3 n_after_collapse = normal(pts[0], pts[1], pts[2]);
+    if(do_opp)
+      n_after_collapse = opp(n_after_collapse);
+
+    const double dotref = product(reference_normal, n_after_collapse);
+    if(dotref < 0)
+      return false;
+    const double dot = product(n_before_collapse, n_after_collapse);
+    if(dot < 0)
+      return false;
+
+//    if (dot * dotref < 0)
+//    {
+//      std::cout << "collapse edge : " << std::endl;
+//      std::cout << point(v0->point()) << " " << point(v1->point()) << std::endl;
+//      std::cout << "facet : " << std::endl;
+//      std::cout << pts[0] << " " << pts[1] << " " << pts[2] << std::endl;
+//
+//      Point_3 c = CGAL::centroid(pts[0], pts[1], pts[2]);
+//      std::cout << "n_before_collapse ";
+//      std::cout << c << " " << (c + n_before_collapse) << std::endl;
+//      std::cout << "n_after_collapse  ";
+//      std::cout << c << " " << (c + n_after_collapse) << std::endl;
+//      std::cout << "reference_normal  ";
+//      std::cout << reference_c << " " << (reference_c + reference_normal) << std::endl;
+//      std::cout << std::endl;
+//    }
+//    if (dotref < 0 || dot < 0)
+//      return false;
+  }
+
+  return true;
+}
+
+template<typename C3t3, typename CellSelector>
+bool are_edge_lengths_valid(const typename C3t3::Edge& edge,
+                            const C3t3& c3t3,
+                            const typename C3t3::Triangulation::Point& new_pos,
+                            const typename C3t3::Triangulation::Geom_traits::FT& sqhigh,
+                            const CellSelector& cell_selector,
+                            const bool /* adaptive */ = false)
+{
+  //SqLengthMap::key_type is Vertex_handle
+  //SqLengthMap::value_type is double
+  typedef typename C3t3::Triangulation::Geom_traits::FT FT;
+  typedef typename C3t3::Edge                           Edge;
+  typedef typename C3t3::Vertex_handle                  Vertex_handle;
+
+  const Vertex_handle v1 = edge.first->vertex(edge.second);
+  const Vertex_handle v2 = edge.first->vertex(edge.third);
+
+  boost::unordered_map<Vertex_handle, FT> edges_sqlength_after_collapse;
+
+  std::vector<Edge> inc_edges;
+  c3t3.triangulation().finite_incident_edges(v1,
+      std::back_inserter(inc_edges));
+  c3t3.triangulation().finite_incident_edges(v2,
+      std::back_inserter(inc_edges));
+
+  for (const Edge& ei : inc_edges)
+  {
+    if (is_outside(ei, c3t3, cell_selector))
+      continue;
+
+    Vertex_handle vh = ei.first->vertex(ei.second);
+    if (vh == v1 || vh == v2)
+      vh = ei.first->vertex(ei.third);
+    if (vh == v1 || vh == v2)
+      continue;
+
+    if (edges_sqlength_after_collapse.find(vh) == edges_sqlength_after_collapse.end())
+    {
+      const FT sqlen = CGAL::squared_distance(new_pos, point(vh->point()));
+
+      //if (adaptive){
+      //  if (is_boundary_edge(ei) || is_hull_edge(ei)){
+      //    if (sqlen_i > split_length)
+      //      return false;
+      //  }
+      //  else if (sqlen_i > 4.*getAimedLength(ei, aimed_length) / 3.){// && is_in_complex(ei)  ){
+      //    return false;
+      //  }
+      //}
+      //else {
+
+      if (sqlen > sqhigh) {
+        return false;
+      }
+      //}
+      edges_sqlength_after_collapse[vh] = sqlen;
+    }
+  }
+
+  return true;
+}
+
+template<typename C3t3>
+void merge_surface_patch_indices(const typename C3t3::Facet& f1,
+                                 const typename C3t3::Facet& f2,
+                                 C3t3& c3t3)
+{
+  const bool in_cx_f1 = c3t3.is_in_complex(f1);
+  const bool in_cx_f2 = c3t3.is_in_complex(f2);
+
+  if (in_cx_f1 && !in_cx_f2)
+  {
+    typename C3t3::Surface_patch_index patch = c3t3.surface_patch_index(f1);
+    f2.first->set_surface_patch_index(f2.second, patch);
+  }
+  else if (in_cx_f2 && !in_cx_f1)
+  {
+    typename C3t3::Surface_patch_index patch = c3t3.surface_patch_index(f2);
+    f1.first->set_surface_patch_index(f1.second, patch);
+  }
+  else if(in_cx_f1 && in_cx_f2)
+  {
+    CGAL_assertion(c3t3.surface_patch_index(f1) == c3t3.surface_patch_index(f2));
+
+    typename C3t3::Surface_patch_index patch = c3t3.surface_patch_index(f2);
+    c3t3.remove_from_complex(f2);
+    f2.first->set_surface_patch_index(f2.second, patch);
+  }
+}
+
+template<typename C3t3>
+typename C3t3::Vertex_handle
+collapse(const typename C3t3::Cell_handle ch,
+         const int to, const int from,
+         C3t3& c3t3)
+{
+  typedef typename C3t3::Triangulation Tr;
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+  typedef typename C3t3::Cell_handle   Cell_handle;
+  typedef typename C3t3::Facet         Facet;
+  typedef typename Tr::Cell_circulator Cell_circulator;
+
+  Tr& tr = c3t3.triangulation();
+
+  Vertex_handle vh0 = ch->vertex(to);
+  Vertex_handle vh1 = ch->vertex(from);
+
+
+  //Update the vertex before removing it
+  std::vector<Cell_handle> find_incident;
+  tr.incident_cells(vh0, std::back_inserter(find_incident));
+
+  std::vector<Cell_handle> cells_to_update;
+  tr.incident_cells(vh1, std::back_inserter(cells_to_update));
+
+  boost::container::small_vector<Cell_handle, 30> inc_cells;
+  Cell_circulator circ = tr.incident_cells(ch, to, from);
+  Cell_circulator done = circ;
+  do
+  {
+    for (int i = 0; i < 4; ++i)
+    {
+      const Vertex_handle vi = circ->vertex(i);
+      if (vi != vh0 && vi != vh1)
+      {
+        const Facet fi(circ, i);
+        if (c3t3.is_in_complex(fi))
+          c3t3.remove_from_complex(fi);
+      }
+    }
+    inc_cells.push_back(circ);
+  }
+  while (++circ != done);
+
+  bool valid = true;
+  std::vector<Cell_handle> cells_to_remove;
+  boost::unordered_set<Cell_handle> invalid_cells;
+
+  for(const Cell_handle c : inc_cells)
+  {
+    const int v0_id = c->index(vh0);
+    const int v1_id = c->index(vh1);
+
+    Cell_handle n0_ch = c->neighbor(v0_id);
+    Cell_handle n1_ch = c->neighbor(v1_id);
+
+    const int ch_id_in_n0 = n0_ch->index(c);
+    const int ch_id_in_n1 = n1_ch->index(c);
+
+    //Merge surface patch indices
+    merge_surface_patch_indices(Facet(n0_ch, ch_id_in_n0),
+                                Facet(n1_ch, ch_id_in_n1),
+                                c3t3);
+
+    //Update neighbors before removing cell
+    n0_ch->set_neighbor(ch_id_in_n0, n1_ch);
+    n1_ch->set_neighbor(ch_id_in_n1, n0_ch);
+
+    //Update vertices cell pointer
+    for (int i = 0; i < 3; i++)
+    {
+      int vid = Tr::vertex_triple_index(ch_id_in_n0, i);
+      n0_ch->vertex(vid)->set_cell(n0_ch);
+    }
+    for (int i = 0; i < 3; i++)
+    {
+      int vid = Tr::vertex_triple_index(ch_id_in_n1, i);
+      n1_ch->vertex(vid)->set_cell(n1_ch);
+    }
+
+    if (tr.is_infinite(n0_ch->vertex(ch_id_in_n0))
+      && tr.is_infinite(n1_ch->vertex(ch_id_in_n1)))
+    {
+      std::cout << "Collapse infinite issue!" << std::endl;
+      return Vertex_handle();
+    }
+    cells_to_remove.push_back(c);
+
+    invalid_cells.insert(c);
+  }
+
+  const Vertex_handle infinite_vertex = tr.infinite_vertex();
+
+  bool v0_updated = false;
+  for (const Cell_handle c : find_incident)
+  {
+    if (invalid_cells.find(c) == invalid_cells.end())//valid cell
+    {
+      if (tr.is_infinite(c))
+        infinite_vertex->set_cell(c);
+      //else {
+      vh0->set_cell(c);
+      v0_updated = true;
+      //}
+    }
+  }
+
+  // update complex edges
+  const std::array<std::array<int, 2>, 6> edges
+    = { { {{0,1}}, {{0,2}}, {{0,3}}, {{1,2}}, {{1,3}}, {{2,3}} } }; //vertex indices in cells
+  const Vertex_handle vkept = vh0;
+  const Vertex_handle vdeleted = vh1;
+  for (const Cell_handle c : cells_to_update)
+  {
+    for (const std::array<int, 2>& ei : edges)
+    {
+      Vertex_handle eiv0 = c->vertex(ei[0]);
+      Vertex_handle eiv1 = c->vertex(ei[1]);
+      if (eiv1 == vdeleted && eiv0 != vkept) //replace eiv1 by vkept
+      {
+        if (c3t3.is_in_complex(eiv0, eiv1))
+        {
+          c3t3.add_to_complex(eiv0, vkept, c3t3.curve_index(eiv0, eiv1));
+          c3t3.remove_from_complex(eiv0, eiv1);
+        }
+      }
+      else if (eiv0 == vdeleted && eiv1 != vkept) //replace eiv0 by vkept
+      {
+        if (c3t3.is_in_complex(eiv0, eiv1))
+        {
+          c3t3.add_to_complex(vkept, eiv1, c3t3.curve_index(eiv0, eiv1));
+          c3t3.remove_from_complex(eiv0, eiv1);
+        }
+      }
+    }
+  }
+
+  // update complex facets
+
+  //Update the vertex before removing it
+  for (const Cell_handle c : cells_to_update)
+  {
+    if (invalid_cells.find(c) == invalid_cells.end()) //valid cell
+    {
+      c->set_vertex(c->index(vh1), vh0);
+
+      if (tr.is_infinite(c))
+        infinite_vertex->set_cell(c);
+      //else {
+      if (!v0_updated) {
+        vh0->set_cell(c);
+        v0_updated = true;
+      }
+      //}
+    }
+  }
+
+  if (!v0_updated)
+    std::cout << "PB i cell not valid!!!" << std::endl;
+
+  // Delete vertex
+  c3t3.triangulation().tds().delete_vertex(vh1);
+
+  // Delete cells
+  for (Cell_handle cell_to_remove : cells_to_remove)
+  {
+    // remove cell
+    if (c3t3.is_in_complex(cell_to_remove))
+      c3t3.remove_from_complex(cell_to_remove);
+    c3t3.triangulation().tds().delete_cell(cell_to_remove);
+  }
+
+  if (!valid){
+    std::cout << "Global triangulation collapse bug!!" << std::endl;
+    return Vertex_handle();
+  }
+
+  return vh0;
+}
+
+
+template<typename C3t3>
+typename C3t3::Vertex_handle collapse(typename C3t3::Edge& edge,
+                                      const Collapse_type& collapse_type,
+                                      C3t3& c3t3)
+{
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+  typedef typename C3t3::Triangulation::Point Point_3;
+
+  Vertex_handle vh0 = edge.first->vertex(edge.second);
+  Vertex_handle vh1 = edge.first->vertex(edge.third);
+
+  const int dim_vh0 = c3t3.in_dimension(vh0);
+  const int dim_vh1 = c3t3.in_dimension(vh1);
+
+  Vertex_handle vh = Vertex_handle();
+
+  const Point_3 p0 = vh0->point();
+  const Point_3 p1 = vh1->point();
+
+  //Collapse at mid point
+  if (collapse_type == TO_MIDPOINT)
+  {
+    Point_3 new_position(CGAL::midpoint(point(vh0->point()), point(vh1->point())));
+    vh0->set_point(new_position);
+    vh1->set_point(new_position);
+
+    vh = collapse(edge.first, edge.second, edge.third, c3t3);
+    c3t3.set_dimension(vh, (std::min)(dim_vh0, dim_vh1));
+  }
+  else //Collapse at vertex
+  {
+    if (collapse_type == TO_V1)
+    {
+      vh0->set_point(p1);
+      vh = collapse(edge.first, edge.third, edge.second, c3t3);
+      c3t3.set_dimension(vh, (std::min)(dim_vh0, dim_vh1));
+    }
+    else //Collapse at v0
+    {
+      if (collapse_type == TO_V0)
+      {
+        vh1->set_point(p0);
+        vh = collapse(edge.first, edge.second, edge.third, c3t3);
+        c3t3.set_dimension(vh, (std::min)(dim_vh0, dim_vh1));
+      }
+      else
+        CGAL_assertion(false);
+    }
+  }
+  return vh;
+}
+
+template<typename C3t3, typename CellSelector, typename Visitor>
+typename C3t3::Vertex_handle collapse_edge(typename C3t3::Edge& edge,
+    C3t3& c3t3,
+    const typename C3t3::Triangulation::Geom_traits::FT& sqhigh,
+    const bool /* protect_boundaries */,
+    CellSelector cell_selector,
+    Visitor& )
+{
+  typedef typename C3t3::Triangulation   Tr;
+  typedef typename Tr::Point             Point;
+  typedef typename Tr::Vertex_handle     Vertex_handle;
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+
+  Collapse_type collapse_type = get_collapse_type(edge, c3t3, cell_selector);
+
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+  const bool in_cx = c3t3.is_in_complex(edge);
+  if (in_cx && collapse_type == IMPOSSIBLE)
+    nb_impossible++;
+#endif
+
+  if (collapse_type == IMPOSSIBLE)
+    return Vertex_handle();
+
+  Point new_pos;
+  switch(collapse_type)
+  {
+  case TO_V0:
+    new_pos = v0->point(); break;
+  case TO_V1:
+    new_pos = v1->point(); break;
+  default:
+    CGAL_assertion(collapse_type == TO_MIDPOINT);
+    new_pos = Point(CGAL::midpoint(point(v0->point()), point(v1->point())));
+  }
+
+  if (!is_valid_collapse(edge, collapse_type, new_pos, c3t3))
+  {
+#ifdef TET_REMESHING_COLLAPSE_FALLBACK_EXPERIMENTS
+    if (collapse_type == TO_MIDPOINT)
+    {
+      // with TO_MIDPOINT, we are authorized to test TO_V0 and TO_V1
+      if (is_valid_collapse(edge, TO_V0, v0->point(), c3t3))
+      {
+        collapse_type = TO_V0;
+        new_pos = v0->point();
+      }
+      else if (is_valid_collapse(edge, TO_V1, v1->point(), c3t3))
+      {
+        collapse_type = TO_V1;
+        new_pos = v1->point();
+      }
+      else
+      {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+        if (in_cx)
+          nb_invalid_collapse++;
+#endif
+        return Vertex_handle();
+      }
+    }
+    else
+#endif //TET_REMESHING_COLLAPSE_FALLBACK_EXPERIMENTS
+    {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+      if (in_cx)
+        nb_invalid_collapse++;
+#endif
+      return Vertex_handle();
+    }
+  }
+
+  if (are_edge_lengths_valid(edge, c3t3, new_pos, sqhigh, cell_selector/*, adaptive = false*/)
+    && collapse_preserves_surface_star(edge, c3t3, new_pos, cell_selector))
+  {
+    CGAL_assertion_code(typename Tr::Cell_handle dc);
+    CGAL_assertion_code(int di);
+    CGAL_assertion_code(int dj);
+    CGAL_assertion(c3t3.triangulation().is_edge(edge.first->vertex(edge.second),
+                                                edge.first->vertex(edge.third), dc, di, dj));
+
+    CollapseTriangulation<C3t3> local_tri(c3t3, edge, collapse_type);
+
+    Result_type res = local_tri.collapse();
+    if (res == VALID)
+    {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+      if (in_cx)
+        nb_valid_collapse++;
+#endif
+      return collapse(edge, collapse_type, c3t3);
+    }
+  }
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+  else if (in_cx)
+    nb_invalid_lengths++;
+#endif
+  return Vertex_handle();
+}
+
+template<typename C3T3, typename CellSelector>
+bool can_be_collapsed(const typename C3T3::Edge& e,
+                      const C3T3& c3t3,
+                      const bool protect_boundaries,
+                      CellSelector cell_selector)
+{
+  if (is_outside(e, c3t3, cell_selector))
+    return false;
+
+  if (protect_boundaries)
+  {
+    if (c3t3.is_in_complex(e))
+      return false;
+    else if (is_boundary(c3t3, e, cell_selector))
+      return false;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    if (!is_internal(e, c3t3, cell_selector))
+    {
+      std::cerr << "e is not inside!?" << std::endl;
+      typename C3T3::Vertex_handle v1 = e.first->vertex(e.second);
+      typename C3T3::Vertex_handle v2 = e.first->vertex(e.third);
+      std::cerr << v1->point() << " " << v2->point() << std::endl;
+    }
+#endif
+
+    CGAL_assertion(is_internal(e, c3t3, cell_selector));
+    return true;
+  }
+  else
+  {
+    return true;
+  }
+}
+
+template<typename C3T3, typename CellSelector, typename Visitor>
+void collapse_short_edges(C3T3& c3t3,
+                          const typename C3T3::Triangulation::Geom_traits::FT& low,
+                          const typename C3T3::Triangulation::Geom_traits::FT& high,
+                          const bool protect_boundaries,
+                          CellSelector cell_selector,
+                          Visitor& visitor)
+{
+  typedef typename C3T3::Triangulation       T3;
+  typedef typename T3::Cell_handle           Cell_handle;
+  typedef typename T3::Edge                  Edge;
+  typedef typename T3::Vertex_handle         Vertex_handle;
+  typedef typename std::pair<Vertex_handle, Vertex_handle> Edge_vv;
+
+  typedef typename T3::Geom_traits     Gt;
+  typedef typename T3::Geom_traits::FT FT;
+  typedef boost::bimap<
+  boost::bimaps::set_of<Edge_vv>,
+        boost::bimaps::multiset_of<FT, std::less<FT> > >  Boost_bimap;
+  typedef typename Boost_bimap::value_type            short_edge;
+
+  T3& tr = c3t3.triangulation();
+  typename Gt::Compute_squared_length_3 sql
+    = tr.geom_traits().compute_squared_length_3_object();
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "Collapse short edges (" << low << ", " << high << ")...";
+  std::cout.flush();
+  std::size_t nb_collapses = 0;
+#endif
+  const FT sq_low = low*low;
+  const FT sq_high = high*high;
+
+  //collect long edges
+  Boost_bimap short_edges;
+  for (const Edge& e : tr.finite_edges())
+  {
+    if (!can_be_collapsed(e, c3t3, protect_boundaries, cell_selector))
+      continue;
+
+    FT sqlen = sql(tr.segment(e));
+    if (sqlen < sq_low)
+      short_edges.insert(short_edge(make_vertex_pair<T3>(e), sqlen));
+  }
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  debug::dump_edges(short_edges, "short_edges.polylines.txt");
+
+  std::ofstream short_success("short_collapse_success.polylines.txt");
+  std::ofstream short_fail("short_collapse_fail.polylines.txt");
+  std::ofstream short_cancel("short_collapse_canceled.polylines.txt");
+#endif
+
+  while(!short_edges.empty())
+  {
+    //the edge with shortest length
+    typename Boost_bimap::right_map::iterator eit = short_edges.right.begin();
+    Edge_vv e = eit->second;
+    short_edges.right.erase(eit);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS
+    FT sqlen = eit->first;
+    std::cout << "\rCollapse... (" << short_edges.left.size() << " short edges, ";
+    std::cout << std::sqrt(sqlen) << ", ";
+    std::cout << nb_collapses << " collapses)";
+    std::cout.flush();
+#endif
+    Cell_handle cell;
+    int i1, i2;
+    if ( tr.tds().is_vertex(e.first)
+         && tr.tds().is_vertex(e.second)
+         && tr.tds().is_edge(e.first, e.second, cell, i1, i2)
+         && tr.segment(Edge(cell, i1, i2)).squared_length() < sq_low)
+    {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+      const typename T3::Point p1 = e.first->point();
+      const typename T3::Point p2 = e.second->point();
+#endif
+
+      Edge edge(cell, i1, i2);
+
+      if (!can_be_collapsed(edge, c3t3, protect_boundaries, cell_selector))
+      {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        short_cancel << "2 " << point(p1) << " " << point(p2) << std::endl;
+#endif
+        continue;
+      }
+
+      Vertex_handle vh = collapse_edge(edge, c3t3, sq_high,
+                                       protect_boundaries, cell_selector,
+                                       visitor);
+      if (vh != Vertex_handle())
+      {
+        std::vector<Edge> incident_short;
+        c3t3.triangulation().finite_incident_edges(vh,
+            std::back_inserter(incident_short));
+        for (const Edge& eshort : incident_short)
+        {
+          if (!can_be_collapsed(eshort, c3t3, protect_boundaries, cell_selector))
+            continue;
+
+          const FT sqlen = sql(tr.segment(eshort));
+          if (sqlen < sq_low)
+            short_edges.insert(short_edge(make_vertex_pair<T3>(eshort), sqlen));
+        }
+
+        //debug::dump_c3t3(c3t3, "dump_after_collapse");
+        //CGAL_assertion(c3t3.triangulation().tds().is_valid());
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+        ++nb_collapses;
+#endif
+      }
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+      if (vh != Vertex_handle())
+        short_success << "2 " << point(p1) << " " << point(p2) << std::endl;
+      else
+        short_fail << "2 " << point(p1) << " " << point(p2) << std::endl;
+#endif
+    }
+  }//end loop on short_edges
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  short_success.close();
+  short_fail.close();
+#endif
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << " done (" << nb_collapses << " collapses)." << std::endl;
+#endif
+}
+}
+}
+}
+
+#endif // CGAL_INTERNAL_COLLAPSE_SHORT_EDGES_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/compute_c3t3_statistics.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/compute_c3t3_statistics.h
new file mode 100644
index 00000000000..15474f84825
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/compute_c3t3_statistics.h
@@ -0,0 +1,214 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_TR_INTERNAL_COMPUTE_C3T3_STATISTICS_H
+#define CGAL_TR_INTERNAL_COMPUTE_C3T3_STATISTICS_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <limits>
+#include <vector>
+#include <algorithm>
+#include <fstream>
+
+#include <boost/unordered_set.hpp>
+
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+template<typename Triangulation, typename CellSelector>
+void compute_statistics(const Triangulation& tr,
+                        CellSelector cell_selector,
+                        const char* filename = "statistics_c3t3.txt")
+{
+  typedef Triangulation Tr;
+  typedef typename Tr::Geom_traits Gt;
+  typedef typename Tr::Cell_handle   Cell_handle;
+  typedef typename Tr::Vertex_handle Vertex_handle;
+  typedef typename Gt::Point_3       Point;
+  typedef typename Tr::Finite_facets_iterator Finite_facets_iterator;
+  typedef typename Tr::Finite_cells_iterator  Finite_cells_iterator;
+  typedef typename Tr::Cell::Subdomain_index  Subdomain_index;
+
+  std::size_t nb_edges = 0;
+  double total_edges = 0;
+  std::size_t nb_angle = 0;
+  double total_angle = 0;
+
+  double min_edges_length = (std::numeric_limits<double>::max)();
+  double max_edges_length = 0.;
+
+  double smallest_edge_radius = (std::numeric_limits<double>::max)();
+  double smallest_radius_radius = (std::numeric_limits<double>::max)();
+  double biggest_v_sma_cube = 0.;
+  double max_dihedral_angle = 0.;
+  double min_dihedral_angle = 180.;
+
+  for (Finite_facets_iterator fit = tr.finite_facets_begin();
+       fit != tr.finite_facets_end(); ++fit)
+  {
+    const Cell_handle cell = fit->first;
+    const int& index = fit->second;
+    if (!cell_selector(cell) || !cell_selector(cell->neighbor(index)))
+      continue;
+
+    const Point& pa = point(cell->vertex((index + 1) & 3)->point());
+    const Point& pb = point(cell->vertex((index + 2) & 3)->point());
+    const Point& pc = point(cell->vertex((index + 3) & 3)->point());
+
+    double edges[3];
+    edges[0] = (CGAL::sqrt(CGAL::squared_distance(pa, pb)));
+    edges[1] = (CGAL::sqrt(CGAL::squared_distance(pa, pc)));
+    edges[2] = (CGAL::sqrt(CGAL::squared_distance(pb, pc)));
+    for (int i = 0; i < 3; ++i)
+    {
+      if (edges[i] < min_edges_length){ min_edges_length = edges[i]; }
+      if (edges[i] > max_edges_length){ max_edges_length = edges[i]; }
+      total_edges += edges[i];
+      ++nb_edges;
+    }
+  }
+
+  double mean_edges_length = total_edges / (double)nb_edges;
+
+  typename Gt::Compute_approximate_dihedral_angle_3 approx_dihedral_angle
+    = tr.geom_traits().compute_approximate_dihedral_angle_3_object();
+
+  std::size_t nb_tets = 0;
+  boost::unordered_set<Vertex_handle> selected_vertices;
+  std::vector<Subdomain_index> sub_ids;
+  for (Finite_cells_iterator cit = tr.finite_cells_begin();
+       cit != tr.finite_cells_end();
+       ++cit)
+  {
+    const Subdomain_index& si = cit->subdomain_index();
+    if (si == Subdomain_index() || !cell_selector(cit))
+      continue;
+
+    ++nb_tets;
+    if (std::find(sub_ids.begin(), sub_ids.end(), si) == sub_ids.end())
+      sub_ids.push_back(cit->subdomain_index());
+    for (int i = 0; i < 4; ++i)
+      selected_vertices.insert(cit->vertex(i));
+
+    const Point& p0 = point(cit->vertex(0)->point());
+    const Point& p1 = point(cit->vertex(1)->point());
+    const Point& p2 = point(cit->vertex(2)->point());
+    const Point& p3 = point(cit->vertex(3)->point());
+    double v = CGAL::abs(tr.tetrahedron(cit).volume());
+    if (v == 0.)
+    {
+      std::cout << "degenerate cell :\n\t";
+      std::cout << p0 << "\n\t" << p1 << "\n\t" << p2 << "\n\t" << p3 << std::endl;
+    }
+    double circumradius = (v == 0.)
+                          ? CGAL::sqrt(CGAL::squared_radius(p0, p1, p2))
+                          : CGAL::sqrt(CGAL::squared_radius(p0, p1, p2, p3));
+
+    //find shortest edge
+    double edges[6];
+    edges[0] = CGAL::sqrt(CGAL::squared_distance(p0, p1));
+    edges[1] = CGAL::sqrt(CGAL::squared_distance(p0, p2));
+    edges[2] = CGAL::sqrt(CGAL::squared_distance(p0, p3));
+    edges[3] = CGAL::sqrt(CGAL::squared_distance(p2, p1));
+    edges[4] = CGAL::sqrt(CGAL::squared_distance(p2, p3));
+    edges[5] = CGAL::sqrt(CGAL::squared_distance(p1, p3));
+
+    double min_edge = edges[0];
+    for (int i = 1; i < 6; ++i)
+    {
+      if (edges[i] < min_edge)
+        min_edge = edges[i];
+    }
+
+    double sumar = CGAL::sqrt(CGAL::squared_area(p0, p1, p2))
+                   + CGAL::sqrt(CGAL::squared_area(p1, p2, p3))
+                   + CGAL::sqrt(CGAL::squared_area(p2, p3, p0))
+                   + CGAL::sqrt(CGAL::squared_area(p3, p1, p0));
+    double inradius = 3. * v / sumar;
+    double smallest_edge_radius_ = min_edge / circumradius*CGAL::sqrt(6.) / 4.;//*sqrt(6)/4 so that the perfect tet ratio is 1
+    double smallest_radius_radius_ = inradius / circumradius * 3.; //*3 so that the perfect tet ratio is 1 instead of 1/3
+    double biggest_v_sma_cube_ = v / std::pow(min_edge, 3) * 6. * CGAL::sqrt(2.);//*6*sqrt(2) so that the perfect tet ratio is 1 instead
+
+    if (smallest_edge_radius_ < smallest_edge_radius)
+      smallest_edge_radius = smallest_edge_radius_;
+
+    if (smallest_radius_radius_ < smallest_radius_radius)
+      smallest_radius_radius = smallest_radius_radius_;
+
+    if (biggest_v_sma_cube_ > biggest_v_sma_cube)
+      biggest_v_sma_cube = biggest_v_sma_cube_;
+
+    double a = CGAL::to_double(CGAL::abs(approx_dihedral_angle(p0, p1, p2, p3)));
+    if (a < min_dihedral_angle) { min_dihedral_angle = a; }
+    if (a > max_dihedral_angle) { max_dihedral_angle = a; }
+    total_angle += a;
+    ++nb_angle;
+    a = CGAL::to_double(CGAL::abs(approx_dihedral_angle(p0, p2, p1, p3)));
+    if (a < min_dihedral_angle) { min_dihedral_angle = a; }
+    if (a > max_dihedral_angle) { max_dihedral_angle = a; }
+    total_angle += a;
+    ++nb_angle;
+    a = CGAL::to_double(CGAL::abs(approx_dihedral_angle(p0, p3, p1, p2)));
+    if (a < min_dihedral_angle) { min_dihedral_angle = a; }
+    if (a > max_dihedral_angle) { max_dihedral_angle = a; }
+    total_angle += a;
+    ++nb_angle;
+    a = CGAL::to_double(CGAL::abs(approx_dihedral_angle(p1, p2, p0, p3)));
+    if (a < min_dihedral_angle) { min_dihedral_angle = a; }
+    if (a > max_dihedral_angle) { max_dihedral_angle = a; }
+    total_angle += a;
+    ++nb_angle;
+    a = CGAL::to_double(CGAL::abs(approx_dihedral_angle(p1, p3, p0, p2)));
+    if (a < min_dihedral_angle) { min_dihedral_angle = a; }
+    if (a > max_dihedral_angle) { max_dihedral_angle = a; }
+    total_angle += a;
+    ++nb_angle;
+    a = CGAL::to_double(CGAL::abs(approx_dihedral_angle(p2, p3, p0, p1)));
+    if (a < min_dihedral_angle) { min_dihedral_angle = a; }
+    if (a > max_dihedral_angle) { max_dihedral_angle = a; }
+    total_angle += a;
+    ++nb_angle;
+  }
+
+  std::size_t nb_subdomains = sub_ids.size();
+  //std::size_t nb_vertices = d->c3t3.number_of_vertices_in_complex();
+
+  std::ofstream ofs(filename);
+  if (!ofs)
+    return;
+
+  ofs << "Nb subdomains               : " << nb_subdomains << std::endl;
+  ofs << "Total number of vertices    : " << tr.number_of_vertices() << std::endl;
+  ofs << "Number of selected cells    : " << nb_tets << std::endl;
+  ofs << "Number of selected vertices : " << selected_vertices.size() << std::endl;
+  ofs << std::endl;
+  ofs << "Min dihedral angle : " << min_dihedral_angle << std::endl;
+  ofs << "Max dihedral angle : " << max_dihedral_angle << std::endl;
+  ofs << std::endl;
+  ofs << "Shortest edge       : " << min_edges_length << std::endl;
+  ofs << "Longest edge        : " << max_edges_length << std::endl;
+  ofs << "Average edge length : " << mean_edges_length << std::endl;
+
+  ofs.close();
+}
+
+}//end namespace internal
+}//end namespace Tetrahedral_remeshing
+}//end namespace CGAL
+
+#endif // CGAL_TR_INTERNAL_COMPUTE_C3T3_STATISTICS_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/flip_edges.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/flip_edges.h
new file mode 100644
index 00000000000..7a31fd3ed20
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/flip_edges.h
@@ -0,0 +1,1198 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_INTERNAL_FLIP_EDGES_H
+#define CGAL_INTERNAL_FLIP_EDGES_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Triangulation_utils_3.h>
+#include <CGAL/utility.h>
+
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+
+#include <boost/unordered_map.hpp>
+#include <boost/unordered_set.hpp>
+#include <boost/container/small_vector.hpp>
+
+#include <limits>
+#include <queue>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+enum Flip_Criterion{ MIN_ANGLE_BASED, AVERAGE_ANGLE_BASED,
+                     VALENCE_BASED, VALENCE_MIN_DH_BASED };
+
+//template<typename VertexPair>
+//void flip_inside_edges(std::vector<VertexPair>&)
+//{
+//  //TODO
+//}
+
+//outer_mirror_facets contains the set of facets of the outer hull
+//of the set of cells modified by the flip operation,
+//"seen from" outside
+//i.e. for each facet f among those, f.first has not been modified by flip
+template<typename C3t3, typename CellSet, typename FacetSet>
+void update_c3t3_facets(C3t3& c3t3,
+                        const CellSet& cells_to_update,
+                        const FacetSet& outer_mirror_facets)
+{
+  typedef typename C3t3::Facet       Facet;
+  typedef typename C3t3::Cell_handle Cell_handle;
+  typedef typename C3t3::Surface_patch_index Surface_patch_index;
+
+  for (Cell_handle c : cells_to_update)
+  {
+    //their subdomain indices have not been modified because we kept the same cells
+    //surface patch indices need to be fixed though
+    for (int i = 0; i < 4; ++i)
+    {
+      const Facet f(c, i);
+      const Facet mf = c3t3.triangulation().mirror_facet(f);
+      if (outer_mirror_facets.find(mf) != outer_mirror_facets.end())
+      {
+        //we are on the border of the modified zone, c3t3 info is valid outside,
+        //on mirror facet
+        const typename C3t3::Surface_patch_index patch = c3t3.surface_patch_index(mf);
+        if (c3t3.is_in_complex(mf))
+          f.first->set_surface_patch_index(f.second, patch);
+        else
+          f.first->set_surface_patch_index(f.second, Surface_patch_index());
+      }
+      else
+      {
+        //we are inside the modified zone, c3t3 info is not valid anymore
+        if (c3t3.is_in_complex(f) || c3t3.is_in_complex(mf))
+        {
+          f.first->set_surface_patch_index(f.second, Surface_patch_index());
+          mf.first->set_surface_patch_index(mf.second, Surface_patch_index());
+        }
+      }
+    }
+  }
+}
+
+template<typename C3t3>
+Sliver_removal_result flip_3_to_2(typename C3t3::Edge& edge,
+                                  C3t3& c3t3,
+                                  const std::vector<typename C3t3::Vertex_handle>& vertices_around_edge,
+                                  const Flip_Criterion& criterion)
+{
+  typedef typename C3t3::Triangulation Tr;
+  typedef typename C3t3::Facet         Facet;
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+  typedef typename C3t3::Cell_handle   Cell_handle;
+  typedef typename Tr::Cell_circulator Cell_circulator;
+  typedef typename Tr::Geom_traits     Gt;
+  typedef typename Gt::FT              FT;
+
+  //Edge to face flip
+  Tr& tr = c3t3.triangulation();
+
+  Cell_circulator circ = tr.incident_cells(edge);
+  Cell_circulator done = circ;
+
+  Vertex_handle vh0 = edge.first->vertex(edge.second);
+  Vertex_handle vh1 = edge.first->vertex(edge.third);
+
+  //Select 2 cells to keep and update and one to remove
+  Cell_handle ch0 = Cell_handle(circ++);
+  Cell_handle ch1 = Cell_handle(circ++);
+  Cell_handle cell_to_remove = Cell_handle(circ++);
+  if (circ != done)
+  {
+    std::cout << "Wrong flip function" << std::endl;
+    return NOT_FLIPPABLE;
+  }
+
+  //Check structural validity
+  Cell_handle c;
+  int i0, i1, i3;
+  if (tr.is_facet(vertices_around_edge[0], vertices_around_edge[1], vertices_around_edge[2],
+                  c, i0, i1, i3))
+    return NOT_FLIPPABLE;
+
+  //Check topological validity
+  const typename C3t3::Subdomain_index subdomain = ch0->subdomain_index();
+  if ( subdomain != ch1->subdomain_index()
+       || subdomain != cell_to_remove->subdomain_index()
+       || ch1->subdomain_index() != cell_to_remove->subdomain_index())
+    return NOT_FLIPPABLE;
+
+  Vertex_handle vh2;
+  Vertex_handle vh3;
+
+  for (int i = 0; i < 3; ++i){
+    if (!ch0->has_vertex(vertices_around_edge[i]))
+      vh2 = vertices_around_edge[i];
+    else if (!ch1->has_vertex(vertices_around_edge[i]))
+      vh3 = vertices_around_edge[i];
+  }
+
+  int vh0_id = ch0->index(vh0);
+  int vh1_id = ch1->index(vh1);
+
+  //Check if flip valid
+  if (!is_well_oriented(tr, vh2,
+                        ch0->vertex(indices(vh0_id, 0)),
+                        ch0->vertex(indices(vh0_id, 1)),
+                        ch0->vertex(indices(vh0_id, 2)))
+      || !is_well_oriented(tr, vh3,
+                           ch1->vertex(indices(vh1_id, 0)),
+                           ch1->vertex(indices(vh1_id, 1)),
+                           ch1->vertex(indices(vh1_id, 2))))
+    return NOT_FLIPPABLE;
+
+  ///********************VALIDITY CHECK***************************/
+  //double curr_min_dh;
+  //bool check_validity = false;
+  //std::vector<typename Tr::Tetrahedron> pre_sliver_Removal_cells;
+  //if (check_validity){
+  //  pre_sliver_Removal_cells.clear();
+  //  pre_sliver_Removal_cells.push_back(K::Tetrahedron_3(ch0->vertex(0)->point(), ch0->vertex(1)->point(), ch0->vertex(2)->point(), ch0->vertex(3)->point()));
+  //  pre_sliver_Removal_cells.push_back(K::Tetrahedron_3(ch1->vertex(0)->point(), ch1->vertex(1)->point(), ch1->vertex(2)->point(), ch1->vertex(3)->point()));
+  //  pre_sliver_Removal_cells.push_back(K::Tetrahedron_3(cell_to_remove->vertex(0)->point(), cell_to_remove->vertex(1)->point(),
+  //    cell_to_remove->vertex(2)->point(), cell_to_remove->vertex(3)->point()));
+
+  //  curr_min_dh = min_dihedral_angle<Gt>(ch0);
+  //  curr_min_dh = std::min(curr_min_dh, min_dihedral_angle<Gt>(ch1));
+  //  curr_min_dh = std::min(curr_min_dh, min_dihedral_angle<Gt>(cell_to_remove));
+
+  //  pre_sliver_Removal_vertices.clear();
+  //  for (int i = 0; i < vertices_around_edge.size(); ++i){
+  //    pre_sliver_Removal_vertices.push_back(Point_3(vertices_around_edge[i]->point()));
+  //  }
+
+  //  previous_edges.clear();
+  //  previous_edges.push_back(std::make_pair(vh0->point(), vh1->point()));
+  //}
+  /*************************************************************/
+
+
+  if (criterion == MIN_ANGLE_BASED)
+  {
+    //Current worst dihedral angle
+    FT curr_min_dh = min_dihedral_angle(tr, ch0);
+    curr_min_dh = (std::min)(curr_min_dh, min_dihedral_angle(tr, ch1));
+    curr_min_dh = (std::min)(curr_min_dh, min_dihedral_angle(tr, cell_to_remove));
+
+    //Result worst dihedral angle
+    if (curr_min_dh > min_dihedral_angle(tr, vh2,
+                                         ch0->vertex(indices(vh0_id, 0)),
+                                         ch0->vertex(indices(vh0_id, 1)),
+                                         ch0->vertex(indices(vh0_id, 2)))
+        || curr_min_dh > min_dihedral_angle(tr, vh3,
+                                            ch1->vertex(indices(vh1_id, 0)),
+                                            ch1->vertex(indices(vh1_id, 1)),
+                                            ch1->vertex(indices(vh1_id, 2))))
+      return NO_BEST_CONFIGURATION;
+  }
+  else if (criterion == AVERAGE_ANGLE_BASED)
+  {
+    //Current worst dihedral angle
+    double average_min_dh = min_dihedral_angle(tr, ch0);
+    average_min_dh += min_dihedral_angle(tr, ch1);
+    average_min_dh += min_dihedral_angle(tr, cell_to_remove);
+
+    average_min_dh /= 3.;
+
+    FT new_average_min_dh = 0.5 *
+                            (min_dihedral_angle(tr, vh2, ch0->vertex(indices(vh0_id, 0)),
+                                ch0->vertex(indices(vh0_id, 1)),
+                                ch0->vertex(indices(vh0_id, 2)))
+                             + min_dihedral_angle(tr, vh3, ch1->vertex(indices(vh1_id, 0)),
+                                 ch1->vertex(indices(vh1_id, 1)),
+                                 ch1->vertex(indices(vh1_id, 2))));
+    //Result worst dihedral angle
+    if (average_min_dh > new_average_min_dh)
+      return NO_BEST_CONFIGURATION;
+  }
+
+  //Keep the facets
+  typedef CGAL::Triple<Vertex_handle, Vertex_handle, Vertex_handle> Facet_vvv;
+  typedef boost::unordered_map<Facet_vvv, std::size_t> FaceMapIndex;
+  boost::unordered_set<Facet> outer_mirror_facets;
+
+  FaceMapIndex facet_map_indices;
+  std::vector<Facet> mirror_facets;
+  circ = Cell_circulator(done);
+  do
+  {
+    // facet opposite to vh0
+    int curr_vh0_id = circ->index(vh0);
+    Facet n_vh0_facet = tr.mirror_facet(Facet(circ, curr_vh0_id));
+
+    outer_mirror_facets.insert(n_vh0_facet);
+
+    Facet_vvv face0 = make_vertex_triple(circ->vertex(indices(curr_vh0_id, 0)),
+                                         circ->vertex(indices(curr_vh0_id, 1)),
+                                         circ->vertex(indices(curr_vh0_id, 2)));
+
+    typename FaceMapIndex::iterator it = facet_map_indices.find(face0);
+    if (it == facet_map_indices.end())
+    {
+      facet_map_indices[face0] = mirror_facets.size();
+      mirror_facets.push_back(n_vh0_facet);
+    }
+
+    // facet opposite to vh1
+    int curr_vh1_id = circ->index(vh1);
+    Facet n_vh1_facet = tr.mirror_facet(Facet(circ, curr_vh1_id));
+
+    outer_mirror_facets.insert(n_vh1_facet);
+
+    Facet_vvv face1 = make_vertex_triple(circ->vertex(indices(curr_vh1_id, 0)),
+                                         circ->vertex(indices(curr_vh1_id, 1)),
+                                         circ->vertex(indices(curr_vh1_id, 2)));
+    it = facet_map_indices.find(face1);
+    if (it == facet_map_indices.end())
+    {
+      facet_map_indices[face1] = mirror_facets.size();
+      mirror_facets.push_back(n_vh1_facet);
+    }
+  }
+  while (++circ != done);
+
+  /*
+  c3t3.remove_from_complex( ch0 );
+  c3t3.remove_from_complex( ch1 );
+  c3t3.remove_from_complex( cell_to_remove );
+
+  tr.flip(edge);
+
+  for( int i = 0 ; i < facets.size() ; i ++ ){
+  Cell_handle new_cell = facets[i].first->neighbor( facets[i].second );
+  c3t3.add_to_complex( new_cell, si );
+  }
+  */
+
+  //Update cells
+  ch0->set_vertex(vh0_id, vh2);
+  ch1->set_vertex(vh1_id, vh3);
+
+  // "New" cells are not created, only modified/updated
+  std::vector<Cell_handle> cells_to_update;
+  cells_to_update.push_back(ch0);
+  cells_to_update.push_back(ch1);
+
+  //Update adjacencies and vertices' cells
+  for (Cell_handle ch : cells_to_update)
+  {
+    for (int v = 0; v < 4; ++v)
+    {
+      Facet_vvv face = make_vertex_triple(ch->vertex(indices(v, 0)),
+                                          ch->vertex(indices(v, 1)),
+                                          ch->vertex(indices(v, 2)));
+      typename FaceMapIndex::iterator it = facet_map_indices.find(face);
+      if (it == facet_map_indices.end())
+      {
+        facet_map_indices[face] = mirror_facets.size();
+        mirror_facets.push_back(Facet(ch, v));
+      }
+      else
+      {
+        Facet mirror_facet = mirror_facets[it->second];
+
+        //Update neighbor
+        mirror_facet.first->set_neighbor(mirror_facet.second, ch);
+        ch->set_neighbor(v, mirror_facet.first);
+      }
+      ch->vertex(v)->set_cell(ch);
+    }
+  }
+
+  // Update c3t3
+  update_c3t3_facets(c3t3, cells_to_update, outer_mirror_facets);
+
+  c3t3.remove_from_complex(cell_to_remove);
+  tr.tds().delete_cell(cell_to_remove);
+
+  /********************VALIDITY CHECK***************************/
+  //if (check_validity)
+  //{
+  //  post_sliver_Removal_cells.clear();
+  //  post_sliver_Removal_cells.push_back(ch0);
+  //  post_sliver_Removal_cells.push_back(ch1);
+
+  //  double new_min_dh = min_dihedral_angle<Gt>(ch0);
+  //  new_min_dh = std::min(new_min_dh, min_dihedral_angle<Gt>(ch1));
+
+  //  post_sliver_Removal_vertices.clear();
+  //  post_sliver_Removal_vertices.push_back(vh2);
+  //  post_sliver_Removal_vertices.push_back(vh3);
+
+  //  if (!is_well_oriented(ch0))
+  //    return INVALID_ORIENTATION;
+  //  if (!is_well_oriented(ch1))
+  //    return INVALID_ORIENTATION;
+  //  if (!tr.is_valid(ch0))
+  //    return INVALID_CELL;
+  //  if (!tr.is_valid(ch1))
+  //    return INVALID_CELL;
+
+  //  for (int i = 0; i < 4; ++i){
+  //    if (!tr.is_valid(ch0->neighbor(i)))
+  //      return INVALID_CELL;
+  //    if (!tr.is_valid(ch1->neighbor(i)))
+  //      return INVALID_CELL;
+  //    if (!tr.tds().is_valid(ch0->vertex(i)))
+  //      return INVALID_VERTEX;
+  //    if (!tr.tds().is_valid(ch1->vertex(i))){
+  //      return INVALID_VERTEX;
+  //    }
+  //  }
+
+  //  if ((curr_min_dh - new_min_dh) > 0.01){
+  //    std::cout << "Three_to_two_flip::Flip not improving the quality: " << curr_min_dh << " to " << new_min_dh << std::endl;
+  //    return INVALID_CELL;
+  //  }
+  //}
+  /***********************************************************/
+
+  return VALID_FLIP;
+}
+
+template<typename C3t3, typename CandidatesQueue>
+void find_best_flip_to_improve_dh(C3t3& c3t3,
+                                  typename C3t3::Edge& edge,
+                                  typename C3t3::Vertex_handle vh2,
+                                  typename C3t3::Vertex_handle vh3,
+                                  CandidatesQueue& candidates,
+                                  double curr_min_dh,
+                                  bool is_sliver_well_oriented = true,
+                                  int e_id = 0)
+{
+  typedef typename C3t3::Triangulation  Tr;
+  typedef typename C3t3::Vertex_handle  Vertex_handle;
+  typedef typename C3t3::Cell_handle    Cell_handle;
+  typedef typename C3t3::Facet          Facet;
+  typedef typename Tr::Facet_circulator Facet_circulator;
+  typedef typename Tr::Cell_circulator  Cell_circulator;
+  typedef typename Tr::Geom_traits      Gt;
+  typedef typename Gt::FT               FT;
+
+  // std::cout << "find_best_flip_to_improve_dh boundary " << std::endl;
+  Tr& tr = c3t3.triangulation();
+
+  Vertex_handle vh0 = edge.first->vertex(edge.second);
+  Vertex_handle vh1 = edge.first->vertex(edge.third);
+
+  Facet_circulator curr_fcirc = tr.incident_facets(edge);
+  Facet_circulator curr_fdone = curr_fcirc;
+
+  //Only keep the possible flips
+  std::vector<Vertex_handle> opposite_vertices;
+  int nb_cells_around_edge = 0;
+  do
+  {
+    Vertex_handle vh;
+    //Get the ids of the opposite vertices
+    for (int i = 0; i < 3; ++i)
+    {
+      Vertex_handle curr_vertex = curr_fcirc->first->vertex(indices(curr_fcirc->second, i));
+      if ( curr_vertex != vh0
+           && curr_vertex != vh1
+           && (curr_vertex == vh2 || curr_vertex == vh3))
+      {
+        vh = curr_vertex;
+        Facet_circulator facet_circulator(curr_fcirc);
+        Facet_circulator facet_done(curr_fcirc);
+
+        facet_done--;
+        facet_circulator++;
+        facet_circulator++;
+
+        bool is_edge = false;
+        do
+        {
+          //Get the ids of the opposite vertices
+          for (int j = 0; j < 3; ++j)
+          {
+            Vertex_handle curr = facet_circulator->first->vertex(
+                                          indices(facet_circulator->second, j));
+            if (curr != vh0  && curr != vh1)
+            {
+              Cell_handle ch;
+              int i0, i1;
+              if (tr.is_edge(curr, vh, ch, i0, i1))
+                is_edge = true;
+            }
+          }
+        } while (++facet_circulator != facet_done);
+
+        if (!is_edge && !tr.is_infinite(vh))
+          opposite_vertices.push_back(vh);
+      }
+    }
+    nb_cells_around_edge++;
+  }
+  while (++curr_fcirc != curr_fdone);
+
+  if (nb_cells_around_edge < 4)
+    return;
+
+  //Facets that will be used to create new cells i.e. all the facets opposite to vh1 and don't have vh
+  //Facets that will be used to update cells i.e. all the facets opposite to vh0 will be set to vh: facet.first->set_vertex( facet.second, vh )
+
+  Cell_circulator cell_circulator = tr.incident_cells(edge);
+  Cell_circulator done = cell_circulator;
+
+  for (std::size_t i = 0; i < opposite_vertices.size(); ++i)
+  {
+    Vertex_handle vh = opposite_vertices[i];
+    bool keep = true;
+
+    std::vector<Facet> facets;
+    do
+    {
+      //Store it if it do not have vh
+      if (!cell_circulator->has_vertex(vh))
+      {
+        //Facets opposite to vh0
+        Facet facet_vh0(cell_circulator, cell_circulator->index(vh0));
+
+        //Facets opposite to vh1
+        Facet facet_vh1(cell_circulator, cell_circulator->index(vh1));
+
+        facets.push_back(facet_vh1);
+        facets.push_back(facet_vh0);
+      }
+    } while (++cell_circulator != done);
+
+
+    FT min_flip_dihedral_angle = (std::numeric_limits<FT>::max)();
+    for (const Facet& fi : facets)
+    {
+      if (!tr.is_infinite(fi.first))
+      {
+        if (is_well_oriented(tr, vh, fi.first->vertex(indices(fi.second, 0)),
+                             fi.first->vertex(indices(fi.second, 1)),
+                             fi.first->vertex(indices(fi.second, 2))))
+        {
+          min_flip_dihedral_angle = (std::min)(min_flip_dihedral_angle,
+                                               min_dihedral_angle(tr, vh, fi.first->vertex(indices(fi.second, 0)),
+                                                   fi.first->vertex(indices(fi.second, 1)),
+                                                   fi.first->vertex(indices(fi.second, 2))));
+        }
+        else
+        {
+          keep = false;
+          break;
+        }
+      }
+    }
+
+    if (keep && (curr_min_dh  < min_flip_dihedral_angle || !is_sliver_well_oriented))
+    {
+      //std::cout << "vh " << vh->info() <<" old " << curr_min_dh << " min " << min_flip_dihedral_angle << std::endl;
+      candidates.push(std::make_pair(min_flip_dihedral_angle, std::make_pair(vh, e_id)));
+    }
+  }
+}
+
+template<typename C3t3, typename CandidatesQueue>
+void find_best_flip_to_improve_dh(C3t3& c3t3,
+                                  typename C3t3::Edge& edge,
+                                  CandidatesQueue& candidates,
+                                  double curr_min_dh,
+                                  bool is_sliver_well_oriented = true,
+                                  int e_id = 0)
+{
+  typedef typename C3t3::Triangulation  Tr;
+  typedef typename C3t3::Vertex_handle  Vertex_handle;
+  typedef typename C3t3::Cell_handle    Cell_handle;
+  typedef typename C3t3::Facet          Facet;
+  typedef typename Tr::Facet_circulator Facet_circulator;
+  typedef typename Tr::Cell_circulator  Cell_circulator;
+  typedef typename Tr::Geom_traits      Gt;
+  typedef typename Gt::FT               FT;
+
+  Tr& tr = c3t3.triangulation();
+
+  Vertex_handle vh0 = edge.first->vertex(edge.second);
+  Vertex_handle vh1 = edge.first->vertex(edge.third);
+
+  Facet_circulator curr_fcirc = tr.incident_facets(edge);
+  Facet_circulator curr_fdone = curr_fcirc;
+
+  //Only keep the possible flips
+  std::vector<Vertex_handle> opposite_vertices;
+  int nb_cells_around_edge = 0;
+  do
+  {
+    Vertex_handle vh;
+    //Get the ids of the opposite vertices
+    for (int i = 0; i < 3; ++i)
+    {
+      Vertex_handle curr_vertex = curr_fcirc->first->vertex(
+                                    indices(curr_fcirc->second, i));
+      if (curr_vertex != vh0 && curr_vertex != vh1)
+      {
+        vh = curr_vertex;
+        break;
+      }
+    }
+
+    Facet_circulator facet_circulator = curr_fcirc;
+    Facet_circulator facet_done = curr_fcirc;
+
+    facet_done--;
+    facet_circulator++;
+    facet_circulator++;
+    bool is_edge = false;
+    do
+    {
+      //Get the ids of the opposite vertices
+      for (int i = 0; i < 3; ++i)
+      {
+        Vertex_handle curr_vertex = facet_circulator->first->vertex(
+                                      indices(facet_circulator->second, i));
+        if (curr_vertex != vh0  && curr_vertex != vh1)
+        {
+          Cell_handle ch;
+          int i0, i1;
+          if (tr.is_edge(curr_vertex, vh, ch, i0, i1))
+            is_edge = true;
+        }
+      }
+    } while (++facet_circulator != facet_done);
+
+    if (!is_edge && !tr.is_infinite(vh))
+      opposite_vertices.push_back(vh);
+
+    nb_cells_around_edge++;
+  }
+  while (++curr_fcirc != curr_fdone);
+  if (nb_cells_around_edge < 4)
+    return;
+
+  //Facets that will be used to create new cells
+  //    i.e. all the facets opposite to vh1 and don't have vh
+  //Facets that will be used to update cells
+  //    i.e. all the facets opposite to vh0 will be set to vh:
+  //    facet.first->set_vertex( facet.second, vh )
+
+  Cell_circulator cell_circulator = tr.incident_cells(edge);
+  Cell_circulator done = cell_circulator;
+
+  for (std::size_t i = 0; i < opposite_vertices.size(); ++i)
+  {
+    Vertex_handle vh = opposite_vertices[i];
+    bool keep = true;
+
+    std::vector<Facet> facets;
+    do
+    {
+      //Store it if it do not have vh
+      if (!cell_circulator->has_vertex(vh))
+      {
+        //Facets opposite to vh0
+        Facet facet_vh0(cell_circulator, cell_circulator->index(vh0));
+
+        //Facets opposite to vh1
+        Facet facet_vh1(cell_circulator, cell_circulator->index(vh1));
+
+        facets.push_back(facet_vh1);
+        facets.push_back(facet_vh0);
+      }
+    }
+    while (++cell_circulator != done);
+
+    FT min_flip_dihedral_angle = (std::numeric_limits<FT>::max)();
+    for (const Facet& fi : facets)
+    {
+      if (!tr.is_infinite(fi.first))
+      {
+        if (is_well_oriented(tr, vh, fi.first->vertex(indices(fi.second, 0)),
+                             fi.first->vertex(indices(fi.second, 1)),
+                             fi.first->vertex(indices(fi.second, 2))))
+        {
+          min_flip_dihedral_angle = (std::min)(min_flip_dihedral_angle,
+                                               min_dihedral_angle(tr, vh, fi.first->vertex(indices(fi.second, 0)),
+                                                   fi.first->vertex(indices(fi.second, 1)),
+                                                   fi.first->vertex(indices(fi.second, 2))));
+        }
+        else
+        {
+          keep = false;
+          break;
+        }
+      }
+    }
+
+    if (keep && (curr_min_dh  < min_flip_dihedral_angle || !is_sliver_well_oriented))
+    {
+      //std::cout << "vh " << vh->info() <<" old " << curr_min_dh << " min " << min_flip_dihedral_angle << std::endl;
+      candidates.push(std::make_pair(min_flip_dihedral_angle, std::make_pair(vh, e_id)));
+    }
+  }
+}
+
+template<typename C3t3, typename Visitor>
+Sliver_removal_result flip_n_to_m(C3t3& c3t3,
+                                  typename C3t3::Edge& edge,
+                                  typename C3t3::Vertex_handle vh,
+                                  Visitor& visitor,
+                                  bool check_validity = false)
+{
+  CGAL_USE(check_validity);
+  // std::cout << "n_to_m_flip::start" << std::endl;
+  typedef typename C3t3::Triangulation  Tr;
+  typedef typename C3t3::Vertex_handle  Vertex_handle;
+  typedef typename C3t3::Cell_handle    Cell_handle;
+  typedef typename C3t3::Facet          Facet;
+  typedef typename Tr::Facet_circulator Facet_circulator;
+  typedef typename Tr::Cell_circulator  Cell_circulator;
+
+  Tr& tr = c3t3.triangulation();
+
+  Vertex_handle vh0 = edge.first->vertex(edge.second);
+  Vertex_handle vh1 = edge.first->vertex(edge.third);
+
+  //This vertex will have its valence augmenting a lot,
+  //TODO take the best one
+
+  //TODO!!!! Check that the created edges do not exist!!!
+
+  Facet_circulator facet_circulator = tr.incident_facets(edge);
+  Facet_circulator done_facet_circulator = facet_circulator;
+  bool look_for_vh_iterator = true;
+  do
+  {
+    facet_circulator++;
+
+    //Get the ids of the opposite vertices
+    for (int i = 0; i < 3; ++i)
+    {
+      if (facet_circulator->first->vertex(indices(facet_circulator->second, i)) == vh)
+        look_for_vh_iterator = false;
+    }
+  } while (facet_circulator != done_facet_circulator && look_for_vh_iterator);
+
+  if (look_for_vh_iterator) {
+    std::cout << "Vertex not an opposite of the edge!!" << std::endl;
+    return NOT_FLIPPABLE;
+  }
+
+  Facet_circulator facet_done(facet_circulator);
+  facet_done--;
+  facet_circulator++;
+  facet_circulator++;
+
+  std::vector<Vertex_handle> vertices_around_edge;
+  do
+  {
+    //Get the ids of the opposite vertices
+    for (int i = 0; i < 3; ++i)
+    {
+      Vertex_handle curr_vertex = facet_circulator->first->vertex(
+                                    indices(facet_circulator->second, i));
+      if (curr_vertex != vh0  && curr_vertex != vh1)
+      {
+        Cell_handle ch;
+        int i0, i1;
+        if (tr.is_edge(curr_vertex, vh, ch, i0, i1))
+          return NOT_FLIPPABLE;
+
+        vertices_around_edge.push_back(curr_vertex);
+      }
+    }
+  } while (++facet_circulator != facet_done);
+
+
+  std::vector<Cell_handle> cells_around_edge;
+  boost::container::small_vector<Cell_handle, 20> to_remove;
+
+  //Neighbors that will need to be updated after flip
+  boost::unordered_set<Facet> neighbor_facets;
+
+  //Facets that will be used to create new cells
+  // i.e. all the facets opposite to vh1 and don't have vh
+  std::vector<Facet> facets_for_new_cells;
+
+  //Facets that will be used to update cells
+  // i.e. all the facets opposite to vh0 will be set to vh :
+  // facet.first->set_vertex( facet.second, vh )
+  std::vector<Facet> facets_for_updated_cells;
+
+  Cell_circulator cell_circulator = tr.incident_cells(edge);
+  Cell_circulator done = cell_circulator;
+  do
+  {
+    cells_around_edge.push_back(cell_circulator);
+
+    //Facets opposite to vh0
+    Facet facet_vh0(cell_circulator, cell_circulator->index(vh0));
+    neighbor_facets.insert(tr.mirror_facet(facet_vh0));
+
+    //Facets opposite to vh1
+    Facet facet_vh1(cell_circulator, cell_circulator->index(vh1));
+    neighbor_facets.insert(tr.mirror_facet(facet_vh1));
+
+    //Store it if it do not have vh
+    if (cell_circulator->has_vertex(vh)) {
+      to_remove.push_back(cell_circulator);
+    }
+    else
+    {
+      facets_for_new_cells.push_back(facet_vh1);
+      facets_for_updated_cells.push_back(facet_vh0);
+    }
+    //
+    //        if( ! is_well_oriented( cell_circulator ) )
+    //            return WRONG;
+  }
+  while (++cell_circulator != done);
+
+  //Check that the result will be valid
+  for (const Facet& fi : facets_for_new_cells)
+  {
+    if ( !tr.is_infinite(fi.first)
+         && !is_well_oriented(tr, vh, fi.first->vertex(indices(fi.second, 0)),
+                              fi.first->vertex(indices(fi.second, 1)),
+                              fi.first->vertex(indices(fi.second, 2))))
+      return NOT_FLIPPABLE;
+  }
+  for (const Facet& fi : facets_for_updated_cells)
+  {
+    if ( !tr.is_infinite(fi.first)
+         && !is_well_oriented(tr, vh, fi.first->vertex(indices(fi.second, 0)),
+                              fi.first->vertex(indices(fi.second, 1)),
+                              fi.first->vertex(indices(fi.second, 2))))
+      return NOT_FLIPPABLE;
+  }
+
+  ///********************VALIDITY CHECK***************************/
+  //double current_min_dh = DBL_MAX;
+
+  //if (check_validity){
+
+  //  pre_sliver_Removal_cells.clear();
+  //  do{
+  //    pre_sliver_Removal_cells.push_back(K::Tetrahedron_3(cell_circulator->vertex(0)->point(), cell_circulator->vertex(1)->point(),
+  //      cell_circulator->vertex(2)->point(), cell_circulator->vertex(3)->point()));
+
+  //    if (!tr.is_infinite(cell_circulator))
+  //      current_min_dh = std::min(current_min_dh, min_dihedral_angle(cell_circulator));
+  //  } while (++cell_circulator != done);
+
+  //  pre_sliver_Removal_vertices.clear();
+  //  pre_sliver_Removal_vertices.push_back(vh->point());
+
+  //  previous_edges.clear();
+  //  previous_edges.push_back(std::make_pair(vh0->point(), vh1->point()));
+  //}
+  ///*************************************************************/
+
+  //Subdomain index?
+  typename C3t3::Subdomain_index subdomain = to_remove[0]->subdomain_index();
+  visitor.before_flip(to_remove[0]);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  for (std::size_t i = 1; i < to_remove.size(); ++i)
+    CGAL_assertion(subdomain == to_remove[i]->subdomain_index());
+#endif
+
+  std::vector<Cell_handle> cells_to_update;
+
+  //Create new cells
+  for (const Facet& fi : facets_for_new_cells)
+  {
+    Cell_handle new_cell = tr.tds().create_cell();
+
+    for (int v = 0; v < 4; v++){
+      new_cell->set_vertex(v, fi.first->vertex(v));
+    }
+
+    new_cell->set_vertex(fi.second, vh);
+
+    c3t3.add_to_complex(new_cell, subdomain);
+    visitor.after_flip(new_cell);
+    cells_to_update.push_back(new_cell);
+  }
+
+  //Update_existing cells
+  for (const Facet& fi : facets_for_updated_cells)
+  {
+    fi.first->set_vertex(fi.second, vh);
+    cells_to_update.push_back(fi.first);
+  }
+
+  typedef CGAL::Triple<Vertex_handle, Vertex_handle, Vertex_handle> Facet_vvv;
+  typedef boost::unordered_map<Facet_vvv, std::size_t> FaceMapIndex;
+
+  FaceMapIndex facet_map_indices;
+  std::vector<Facet> facets;
+
+  for (const Facet& f : neighbor_facets)
+  {
+    Cell_handle ch = f.first;
+    int v = f.second;
+
+    Facet_vvv face = make_vertex_triple(ch->vertex(indices(v,0)),
+                                        ch->vertex(indices(v,1)),
+                                        ch->vertex(indices(v,2)));
+    typename FaceMapIndex::iterator it = facet_map_indices.find(face);
+    if (it == facet_map_indices.end())
+    {
+      facet_map_indices[face] = facets.size();
+      facets.push_back(Facet(ch, v));
+    }
+  }
+
+  //Update adjacencies and vertices cells
+  for (Cell_handle ch : cells_to_update)
+  {
+    for (int v = 0; v < 4; v++)
+    {
+      Facet_vvv face = make_vertex_triple(ch->vertex(indices(v,0)),
+                                          ch->vertex(indices(v,1)),
+                                          ch->vertex(indices(v,2)));
+      typename FaceMapIndex::iterator it = facet_map_indices.find(face);
+      if (it == facet_map_indices.end())
+      {
+        facet_map_indices[face] = facets.size();
+        facets.push_back(Facet(ch, v));
+      }
+      else
+      {
+        Facet facet = facets[it->second];
+
+        //Update neighbor
+        facet.first->set_neighbor(facet.second, ch);
+        ch->set_neighbor(v, facet.first);
+      }
+      ch->vertex(v)->set_cell(ch);
+    }
+  }
+
+  // Update c3t3
+  update_c3t3_facets(c3t3, cells_to_update, neighbor_facets);
+
+  //Remove cells
+  for (Cell_handle ch : to_remove)
+  {
+    c3t3.remove_from_complex(ch);
+    tr.tds().delete_cell(ch);
+  }
+
+  ///********************VALIDITY CHECK***************************/
+  //if (check_validity){
+
+  //  double new_min_dh = DBL_MAX;
+
+  //  post_sliver_Removal_cells.clear();
+  //  for (unsigned int i = 0; i < cells_to_update.size(); ++i){
+  //    post_sliver_Removal_cells.push_back(cells_to_update[i]);
+
+  //    if (!tr.is_infinite(cells_to_update[i]))
+  //      new_min_dh = std::min(new_min_dh, min_dihedral_angle(cells_to_update[i]));
+  //  }
+
+  //  post_sliver_Removal_vertices.clear();
+  //  for (unsigned int i = 0; i < vertices_around_edge.size(); ++i){
+  //    post_sliver_Removal_vertices.push_back(vertices_around_edge[i]);
+  //  }
+
+  //  current_edges.clear();
+  //  for (unsigned int i = 0; i < vertices_around_edge.size(); ++i){
+  //    current_edges.push_back(std::make_pair(vertices_around_edge[i]->point(), vh->point()));
+  //  }
+
+
+  //  for (unsigned int i = 0; i < cells_to_update.size(); ++i){
+  //    if (!tr.is_valid(cells_to_update[i]))
+  //      return INVALID_CELL;
+
+  //    for (int v = 0; v < 4; v++){
+  //      if (!tr.is_valid(cells_to_update[i]->neighbor(v)))
+  //        return INVALID_CELL;
+
+  //      if (!tr.tds().is_valid(cells_to_update[i]->vertex(v)))
+  //        return INVALID_VERTEX;
+
+  //    }
+  //  }
+
+  //  if ((current_min_dh - new_min_dh) > 0.01){
+  //    std::cout << pre_sliver_Removal_cells.size() << " to " << post_sliver_Removal_cells.size() << " flip not improving the quality: " <<
+  //      current_min_dh << " to " << new_min_dh << std::endl;
+  //    return INVALID_CELL;
+  //  }
+
+  //}
+  ///***********************************************************/
+
+  // std::cout << "n_to_m_flip::end with success" << std::endl;
+
+  return VALID_FLIP;
+}
+
+
+template<typename C3t3, typename Visitor>
+Sliver_removal_result flip_n_to_m(typename C3t3::Edge& edge,
+                                  C3t3& c3t3,
+                                  std::vector<typename C3t3::Vertex_handle>& boundary_vertices,
+                                  const Flip_Criterion& criterion,
+                                  Visitor& visitor)
+{
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+  typedef typename C3t3::Triangulation::Geom_traits Gt;
+  typedef typename Gt::FT FT;
+  typename C3t3::Triangulation& tr = c3t3.triangulation();
+
+  Sliver_removal_result result = NOT_FLIPPABLE;
+
+  typedef std::pair<double, std::pair<Vertex_handle, int> > Angle_and_vertex;
+
+  //std::cout << "n_to_m_flip " << boundary_vertices.size() << std::endl;
+  if (criterion == MIN_ANGLE_BASED)
+  {
+    std::priority_queue<Angle_and_vertex> candidates;
+
+    Cell_circulator circ = c3t3.triangulation().incident_cells(edge);
+    Cell_circulator done = circ;
+
+    FT curr_min_dh = min_dihedral_angle(tr, circ++);
+    while (circ != done)
+    {
+      curr_min_dh = (std::min)(curr_min_dh, min_dihedral_angle(tr, circ++));
+    }
+    if (boundary_vertices.size() == 2)
+      find_best_flip_to_improve_dh(c3t3, edge, boundary_vertices[0], boundary_vertices[1],
+                                   candidates, curr_min_dh);
+    else
+      find_best_flip_to_improve_dh(c3t3, edge, candidates, curr_min_dh);
+
+    bool flip_performed = false;
+    while (!candidates.empty() && !flip_performed)
+    {
+      Angle_and_vertex curr_cost_vpair = candidates.top();
+      candidates.pop();
+
+      //std::cout << curr_min_dh << " old, current " << curr_cost_vpair.second.first->info() <<" and angle " << curr_cost_vpair.first << std::endl;
+
+      if (curr_min_dh >= curr_cost_vpair.first)
+        return NO_BEST_CONFIGURATION;
+
+      result = flip_n_to_m(c3t3, edge, curr_cost_vpair.second.first, visitor);
+
+      if (result != NOT_FLIPPABLE)
+        flip_performed = true;
+    }
+  }
+
+  return result;
+}
+
+template<typename C3t3, typename Visitor>
+Sliver_removal_result find_best_flip(typename C3t3::Edge& edge,
+                                     C3t3& c3t3,
+                                     const Flip_Criterion& criterion,
+                                     Visitor& visitor)
+{
+  typedef typename C3t3::Triangulation        Tr;
+  typedef typename C3t3::Vertex_handle        Vertex_handle;
+  typedef typename Tr::Facet_circulator       Facet_circulator;
+
+  Tr& tr = c3t3.triangulation();
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+
+  Facet_circulator circ = tr.incident_facets(edge);
+  Facet_circulator done = circ;
+
+  //Identify the vertices around this edge
+  boost::unordered_set<Vertex_handle> vertices_around_edge;
+  bool boundary_edge = false;
+  bool hull_edge = false;
+
+  boost::unordered_set<Vertex_handle> boundary_vertices;
+//  boost::unordered_set<Vertex_handle> hull_vertices;
+  do
+  {
+    //Get the ids of the opposite vertices
+    for (int i = 0; i < 3; ++i)
+    {
+      Vertex_handle vi = circ->first->vertex(indices(circ->second, i));
+      if (vi != v0 && vi != v1)
+      {
+        vertices_around_edge.insert(vi);
+
+        if ( circ->first->subdomain_index()
+             != circ->first->neighbor(circ->second)->subdomain_index())
+        {
+          boundary_edge = true;
+          boundary_vertices.insert(vi);
+        }
+
+        if ( tr.is_infinite(circ->first)
+             != tr.is_infinite(circ->first->neighbor(circ->second)))
+        {
+          hull_edge = true;
+          //hull_vertices.insert(vi);
+        }
+      }
+    }
+  }
+  while (++circ != done);
+
+
+  //Check if not feature edge
+  if (boundary_vertices.size() > 2)
+    return NOT_FLIPPABLE;
+
+  // perform flip when possible
+  Sliver_removal_result res = NOT_FLIPPABLE;
+  if (vertices_around_edge.size() == 3)
+  {
+    if (!boundary_edge && !hull_edge)
+    {
+      std::vector<Vertex_handle> vertices;
+      vertices.insert(vertices.end(), vertices_around_edge.begin(), vertices_around_edge.end());
+      res = flip_3_to_2(edge, c3t3, vertices, criterion);
+    }
+  }
+  else
+  {
+    //TODO fix for hull edges
+    // if( hull_edge )
+    //    return n_to_m_flip( edge, hull_vertices, flip_criterion, check_validity );
+    if (!hull_edge)
+    {
+      std::vector<Vertex_handle> vertices;
+      vertices.insert(vertices.end(), boundary_vertices.begin(), boundary_vertices.end());
+      res = flip_n_to_m(edge, c3t3, vertices, criterion, visitor);
+      //return n_to_m_flip(edge, boundary_vertices, flip_criterion);
+    }
+  }
+
+
+  return res;
+}
+
+
+template<typename VertexPair, typename C3t3, typename Visitor>
+std::size_t flip_all_edges(const std::vector<VertexPair>& edges,
+                           C3t3& c3t3,
+                           const Flip_Criterion& criterion,
+                           Visitor& visitor)
+{
+  typedef typename C3t3::Triangulation Tr;
+  typedef typename Tr::Cell_handle   Cell_handle;
+  typedef typename Tr::Edge          Edge;
+
+  Tr& tr = c3t3.triangulation();
+
+  std::size_t count = 0;
+  for (const VertexPair vp : edges)
+  {
+    Cell_handle ch;
+    int i0, i1;
+    if (tr.is_edge(vp.first, vp.second, ch, i0, i1))
+    {
+      Edge edge(ch, i0, i1);
+
+      Sliver_removal_result res = find_best_flip(edge, c3t3, criterion, visitor);
+      if (res == INVALID_CELL || res == INVALID_VERTEX || res == INVALID_ORIENTATION)
+      {
+        std::cout << "FLIP PROBLEM!!!!" << std::endl;
+        return count;
+      }
+      if (res == VALID_FLIP)
+      {
+        ++count;
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS
+        std::cout << "\rFlip... (";
+        std::cout << count << " flips)";
+        std::cout.flush();
+#endif
+      }
+    }
+  }
+  return count;
+}
+
+template<typename C3T3, typename CellSelector, typename Visitor>
+void flip_edges(C3T3& c3t3,
+                const bool protect_boundaries,
+                CellSelector cell_selector,
+                Visitor& visitor)
+{
+  CGAL_USE(protect_boundaries);
+  typedef typename C3T3::Triangulation       T3;
+  typedef typename T3::Vertex_handle         Vertex_handle;
+  typedef typename std::pair<Vertex_handle, Vertex_handle> Edge_vv;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "Flip edges...";
+  std::cout.flush();
+  std::size_t nb_flips = 0;
+#endif
+
+  //const Flip_Criterion criterion = VALENCE_MIN_DH_BASED;
+
+  //collect long edges
+
+  //compute vertices normals map?
+
+  // typedef typename C3T3::Surface_patch_index Surface_patch_index;
+  // typedef boost::unordered_map<Surface_patch_index, unsigned int> Spi_map;
+  //if (!protect_boundaries)
+  //{
+  //  std::cout << "\tBoundary flips" << std::endl;
+  //  //Boundary flip
+  //  std::vector<Spi_map> boundary_vertices_valences;
+  //  std::vector<Edge_vv> boundary_edges;
+
+  //  collectBoundaryEdges(boundary_edges);
+
+  //  computeVerticesValences(boundary_vertices_valences);
+
+  //  if (criterion == VALENCE_BASED)
+  //    flipBoundaryEdges(boundary_edges, boundary_vertices_valences, VALENCE_BASED);
+  //  else
+  //    flipBoundaryEdges(boundary_edges, boundary_vertices_valences, MIN_ANGLE_BASED);
+  //}
+
+  std::vector<Edge_vv> inside_edges;
+  get_internal_edges(c3t3,
+                     cell_selector,
+                     std::back_inserter(inside_edges));
+
+  //if (criterion == VALENCE_BASED)
+  //  flip_inside_edges(inside_edges);
+  //else
+  //{
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  nb_flips =
+#endif
+    flip_all_edges(inside_edges, c3t3, MIN_ANGLE_BASED, visitor);
+  //}
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << " done (" << nb_flips << " flips)." << std::endl;
+#endif
+}
+
+}//namespace internal
+}//namespace Tetrahedral_remeshing
+}//namespace CGAL
+
+#endif // CGAL_INTERNAL_FLIP_EDGES_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/smooth_vertices.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/smooth_vertices.h
new file mode 100644
index 00000000000..04e20d13d92
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/smooth_vertices.h
@@ -0,0 +1,713 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_INTERNAL_SMOOTH_VERTICES_H
+#define CGAL_INTERNAL_SMOOTH_VERTICES_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Vector_3.h>
+
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+#include <CGAL/Tetrahedral_remeshing/internal/FMLS.h>
+
+#include <boost/unordered_map.hpp>
+#include <boost/optional.hpp>
+#include <boost/container/small_vector.hpp>
+
+#include <vector>
+#include <cmath>
+#include <list>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+template<typename C3t3>
+class Tetrahedral_remeshing_smoother
+{
+  typedef typename C3t3::Triangulation       Tr;
+  typedef typename C3t3::Surface_patch_index Surface_patch_index;
+  typedef typename Tr::Vertex_handle         Vertex_handle;
+  typedef typename Tr::Edge                  Edge;
+  typedef typename Tr::Facet                 Facet;
+
+  typedef typename Tr::Geom_traits           Gt;
+  typedef typename Gt::Vector_3              Vector_3;
+  typedef typename Gt::Point_3               Point_3;
+
+private:
+  typedef  CGAL::Tetrahedral_remeshing::internal::FMLS<Gt> FMLS;
+  std::vector<FMLS> subdomain_FMLS;
+  boost::unordered_map<Surface_patch_index, std::size_t> subdomain_FMLS_indices;
+
+public:
+  template<typename CellSelector>
+  void init(const C3t3& c3t3, const CellSelector& cell_selector)
+  {
+    //collect a map of vertices surface indices
+    boost::unordered_map<Vertex_handle, std::vector<Surface_patch_index> > vertices_surface_indices;
+    collect_vertices_surface_indices(c3t3, vertices_surface_indices);
+
+    //collect a map of normals at surface vertices
+    boost::unordered_map<Vertex_handle,
+          boost::unordered_map<Surface_patch_index, Vector_3> > vertices_normals;
+    compute_vertices_normals(c3t3, vertices_normals, cell_selector);
+
+    // Build MLS Surfaces
+    createMLSSurfaces(subdomain_FMLS,
+                      subdomain_FMLS_indices,
+                      vertices_normals,
+                      vertices_surface_indices,
+                      c3t3);
+  }
+
+private:
+
+  Vector_3 project_on_tangent_plane(const Vector_3& gi,
+                                    const Vector_3& pi,
+                                    const Vector_3& normal)
+  {
+    Vector_3 diff = pi - gi;
+    return gi + (normal * diff) * normal;
+  }
+
+  template<typename CellSelector>
+  boost::optional<Facet>
+  find_adjacent_facet_on_surface(const Facet& f,
+                                 const Edge& edge,
+                                 const C3t3& c3t3,
+                                 const CellSelector& cell_selector)
+  {
+    CGAL_assertion(is_boundary(c3t3, f, cell_selector));
+
+    typedef typename Tr::Facet_circulator Facet_circulator;
+
+    if (c3t3.is_in_complex(edge))
+      return {}; //do not "cross" complex edges
+    //they are likely to be sharp and not to follow the > 0 dot product criterion
+
+    const Surface_patch_index& patch = c3t3.surface_patch_index(f);
+    const Facet& mf = c3t3.triangulation().mirror_facet(f);
+
+    Facet_circulator fcirc = c3t3.triangulation().incident_facets(edge);
+    Facet_circulator fend = fcirc;
+    do
+    {
+      const Facet fi = *fcirc;
+      if (f != fi
+          && mf != fi
+          && is_boundary(c3t3, fi, cell_selector)
+          && patch == c3t3.surface_patch_index(fi))
+      {
+        return canonical_facet(fi); //"canonical" is important
+      }
+    } while (++fcirc != fend);
+
+    return {};
+  }
+
+  template<typename Gt>
+  Vector_3 compute_normal(const Facet& f,
+                          const Vector_3& reference_normal,
+                          const Gt& gt)
+  {
+    typename Gt::Construct_opposite_vector_3
+      opp = gt.construct_opposite_vector_3_object();
+    typename Gt::Compute_scalar_product_3
+      scalar_product = gt.compute_scalar_product_3_object();
+
+    Vector_3 n = CGAL::Tetrahedral_remeshing::normal(f, gt);
+    if (scalar_product(n, reference_normal) < 0.)
+      n = opp(n);
+
+    return n;
+  }
+
+  template<typename VertexNormalsMap, typename CellSelector>
+  void compute_vertices_normals(const C3t3& c3t3,
+                                VertexNormalsMap& normals_map,
+                                const CellSelector& cell_selector)
+  {
+    typename Tr::Geom_traits gt = c3t3.triangulation().geom_traits();
+    typename Tr::Geom_traits::Construct_opposite_vector_3
+      opp = gt.construct_opposite_vector_3_object();
+
+    const Tr& tr = c3t3.triangulation();
+
+    //collect all facet normals
+    boost::unordered_map<Facet, Vector_3> fnormals;
+    for (const Facet& f : tr.finite_facets())
+    {
+      if (is_boundary(c3t3, f, cell_selector))
+      {
+        const Facet cf = canonical_facet(f);
+        fnormals[cf] = CGAL::NULL_VECTOR;
+      }
+    }
+
+    for (const std::pair<Facet, Vector_3>& fn : fnormals)
+    {
+      if(fn.second != CGAL::NULL_VECTOR)
+        continue;
+
+      const Facet& f = fn.first;
+      const Facet& mf = tr.mirror_facet(f);
+      CGAL_assertion(is_boundary(c3t3, f, cell_selector));
+
+      Vector_3 start_ref = CGAL::Tetrahedral_remeshing::normal(f, tr.geom_traits());
+      if (c3t3.triangulation().is_infinite(mf.first)
+          || c3t3.subdomain_index(mf.first) < c3t3.subdomain_index(f.first))
+        start_ref = opp(start_ref);
+      fnormals[f] = start_ref;
+
+      std::list<Facet> facets;
+      facets.push_back(f);
+      while (!facets.empty())
+      {
+        const Facet ff = facets.front();
+        facets.pop_front();
+
+        const typename C3t3::Cell_handle ch = f.first;
+        const std::array<std::array<int, 2>, 3> edges
+          = {{ {{(ff.second + 1) % 4, (ff.second + 2) % 4}}, //edge 1-2
+               {{(ff.second + 2) % 4, (ff.second + 3) % 4}}, //edge 2-3
+               {{(ff.second + 3) % 4, (ff.second + 1) % 4}}  //edge 3-1
+            }}; //vertex indices in cells
+
+        const Vector_3& ref = fnormals[f];
+        for (const std::array<int, 2>& ei : edges)
+        {
+          Edge edge(ch, ei[0], ei[1]);
+          if (boost::optional<Facet> neighbor
+              = find_adjacent_facet_on_surface(f, edge, c3t3, cell_selector))
+          {
+            const Facet neigh = *neighbor; //already a canonical_facet
+            if (fnormals[neigh] == CGAL::NULL_VECTOR) //check it's not already computed
+            {
+              fnormals[neigh] = compute_normal(neigh, ref, gt);
+              facets.push_back(neigh);
+            }
+          }
+        }
+      }
+    }
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    std::ofstream osf("dump_facet_normals.polylines.txt");
+#endif
+    for (const auto& fn : fnormals)
+    {
+      const Facet& f = fn.first;
+      const Vector_3& n = fn.second;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+      typename Tr::Geom_traits::Point_3 fc
+        = CGAL::centroid(point(f.first->vertex(indices(f.second, 0))->point()),
+                         point(f.first->vertex(indices(f.second, 1))->point()),
+                         point(f.first->vertex(indices(f.second, 2))->point()));
+      osf << "2 " << fc << " " << (fc + n) << std::endl;
+#endif
+      const Surface_patch_index& surf_i = c3t3.surface_patch_index(f);
+
+      for (int i = 0; i < 3; ++i)
+      {
+        const Vertex_handle vi = f.first->vertex(indices(f.second, i));
+        typename VertexNormalsMap::iterator patch_vector_it = normals_map.find(vi);
+
+        if (patch_vector_it == normals_map.end()
+            || patch_vector_it->second.find(surf_i) == patch_vector_it->second.end())
+        {
+          normals_map[vi][surf_i] = n;
+        }
+        else
+        {
+          normals_map[vi][surf_i] += n;
+        }
+      }
+    }
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    osf.close();
+    std::ofstream os("dump_normals.polylines.txt");
+    boost::unordered_map<Surface_patch_index,
+          std::vector<typename Tr::Geom_traits::Segment_3 > > ons_map;
+#endif
+
+    //normalize the computed normals
+    for (typename VertexNormalsMap::iterator vnm_it = normals_map.begin();
+         vnm_it != normals_map.end(); ++vnm_it)
+    {
+      //value type is map<Surface_patch_index, Vector_3>
+      for (typename VertexNormalsMap::mapped_type::iterator it = vnm_it->second.begin();
+           it != vnm_it->second.end(); ++it)
+      {
+        Vector_3& n = it->second;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        auto p = point(vnm_it->first->point());
+        os << "2 " << p << " " << (p + n) << std::endl;
+#endif
+
+        CGAL::Tetrahedral_remeshing::normalize(n, c3t3.triangulation().geom_traits());
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        const Surface_patch_index si = it->first;
+        if (ons_map.find(si) == ons_map.end())
+          ons_map[si] = std::vector<typename Tr::Geom_traits::Segment_3>();
+        ons_map[si].push_back(typename Tr::Geom_traits::Segment_3(p, p + n));
+#endif
+      }
+    }
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    os.close();
+    for (auto& kv : ons_map)
+    {
+      std::ostringstream oss;
+      oss << "dump_normals_normalized_" << kv.first << ".polylines.txt";
+      std::ofstream ons(oss.str());
+      for (auto s : kv.second)
+        ons << "2 " << s.source() << " " << s.target() << std::endl;
+      ons.close();
+    }
+#endif
+  }
+
+  boost::optional<Vector_3> project(const Surface_patch_index& si,
+                                    const Vector_3& gi)
+  {
+    CGAL_assertion(subdomain_FMLS_indices.find(si) != subdomain_FMLS_indices.end());
+    CGAL_assertion(!std::isnan(gi.x()) && !std::isnan(gi.y()) && !std::isnan(gi.z()));
+
+    Vector_3 point(gi.x(), gi.y(), gi.z());
+    Vector_3 res_normal = CGAL::NULL_VECTOR;
+    Vector_3 result(point);
+
+    const FMLS& fmls = subdomain_FMLS[subdomain_FMLS_indices.at(si)];
+
+    int it_nb = 0;
+    const int max_it_nb = 5;
+    const double epsilon = fmls.getPNScale() / 1000.;
+    const double sq_eps = CGAL::square(epsilon);
+
+    do
+    {
+      point = result;
+
+      fmls.fastProjectionCPU(point, result, res_normal);
+
+      if (std::isnan(result[0]) || std::isnan(result[1]) || std::isnan(result[2])) {
+        std::cout << "MLS error detected si " //<< si
+                  << "\t(size : "       << fmls.getPNSize() << ")"
+                  << "\t(point = "      << point      << " )" << std::endl;
+        return {};
+      }
+    } while ((result - point).squared_length() > sq_eps && ++it_nb < max_it_nb);
+
+    return Vector_3(result[0], result[1], result[2]);
+  }
+
+  template<typename CellRange, typename Tr>
+  void check_inversion_and_move(const typename Tr::Vertex_handle v,
+                                const typename Tr::Point& final_pos,
+                                const CellRange& inc_cells,
+                                const Tr& /* tr */)
+  {
+    const typename Tr::Point backup = v->point(); //backup v's position
+    const typename Tr::Geom_traits::Point_3 pv = point(backup);
+
+    bool valid_orientation = false;
+    double frac = 1.0;
+    typename Tr::Geom_traits::Vector_3 move(pv, point(final_pos));
+    do
+    {
+      v->set_point(typename Tr::Point(pv + frac * move));
+
+      bool valid_try = true;
+      for (const typename Tr::Cell_handle ci : inc_cells)
+      {
+        if (CGAL::POSITIVE != CGAL::orientation(point(ci->vertex(0)->point()),
+                                                point(ci->vertex(1)->point()),
+                                                point(ci->vertex(2)->point()),
+                                                point(ci->vertex(3)->point())))
+        {
+          frac = 0.9 * frac;
+          valid_try = false;
+          break;
+        }
+      }
+      valid_orientation = valid_try;
+
+//          std::cout << std::boolalpha << "valid orientation = " << valid_orientation
+//                    << "\tfrac = " << frac << std::endl;
+    }
+    while(!valid_orientation && frac > 0.1);
+
+    if (!valid_orientation) //move failed
+      v->set_point(backup);
+  }
+
+  void collect_vertices_surface_indices(
+    const C3t3& c3t3,
+    boost::unordered_map<Vertex_handle,
+    std::vector<Surface_patch_index> >& vertices_surface_indices)
+  {
+    for (typename C3t3::Facets_in_complex_iterator
+         fit = c3t3.facets_in_complex_begin();
+         fit != c3t3.facets_in_complex_end(); ++fit)
+    {
+      const Surface_patch_index& surface_index = c3t3.surface_patch_index(*fit);
+
+      for (int i = 0; i < 3; i++)
+      {
+        const Vertex_handle vi = fit->first->vertex(indices(fit->second, i));
+
+        std::vector<Surface_patch_index>& v_surface_indices = vertices_surface_indices[vi];
+        if (std::find(v_surface_indices.begin(), v_surface_indices.end(), surface_index) == v_surface_indices.end())
+          v_surface_indices.push_back(surface_index);
+      }
+    }
+  }
+
+public:
+  template<typename C3T3, typename CellSelector>
+  void smooth_vertices(C3T3& c3t3,
+                       const bool protect_boundaries,
+                       const CellSelector& cell_selector)
+  {
+    typedef typename C3T3::Cell_handle            Cell_handle;
+    typedef typename Gt::FT              FT;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    std::ofstream os_surf("smooth_surfaces.polylines.txt");
+    std::ofstream os_surf0("smooth_surfaces0.polylines.txt");
+    std::ofstream os_vol("smooth_volume.polylines.txt");
+#endif
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+    std::cout << "Smooth vertices...";
+    std::cout.flush();
+    std::size_t nb_done = 0;
+#endif
+
+    Tr& tr = c3t3.triangulation();
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_SMOOTH_SHARP_EDGES
+    //collect a map of vertices surface indices
+    boost::unordered_map<Vertex_handle, std::vector<Surface_patch_index> > vertices_surface_indices;
+    collect_vertices_surface_indices(c3t3, vertices_surface_indices);
+#endif
+    //collect a map of normals at surface vertices
+    boost::unordered_map<Vertex_handle,
+          boost::unordered_map<Surface_patch_index, Vector_3> > vertices_normals;
+    compute_vertices_normals(c3t3, vertices_normals, cell_selector);
+
+    //smooth()
+    const std::size_t nbv = tr.number_of_vertices();
+    boost::unordered_map<Vertex_handle, std::size_t> vertex_id;
+    std::vector<Vector_3> smoothed_positions(nbv, CGAL::NULL_VECTOR);
+    std::vector<int> neighbors(nbv, -1);
+
+    //collect ids
+    std::size_t id = 0;
+    for (const Vertex_handle v : tr.finite_vertex_handles())
+    {
+      vertex_id[v] = id++;
+    }
+
+    //collect incident cells
+    std::vector<boost::container::small_vector<Cell_handle, 40> >
+    inc_cells(nbv, boost::container::small_vector<Cell_handle, 40>());
+    for (const Cell_handle c : tr.finite_cell_handles())
+    {
+      for (int i = 0; i < 4; ++i)
+      {
+        const std::size_t idi = vertex_id[c->vertex(i)];
+        inc_cells[idi].push_back(c);
+      }
+    }
+
+    if (!protect_boundaries)
+    {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_SMOOTH_SHARP_EDGES
+      /////////////// EDGES IN COMPLEX //////////////////
+      //collect neighbors
+      for (const Edge& e : tr.finite_edges())
+      {
+        if (c3t3.is_in_complex(e))
+        {
+          const Vertex_handle vh0 = e.first->vertex(e.second);
+          const Vertex_handle vh1 = e.first->vertex(e.third);
+
+          const std::size_t& i0 = vertex_id.at(vh0);
+          const std::size_t& i1 = vertex_id.at(vh1);
+
+          const bool on_feature_v0 = is_on_feature(vh0);
+          const bool on_feature_v1 = is_on_feature(vh1);
+
+          if (!c3t3.is_in_complex(vh0))
+            neighbors[i0] = (std::max)(0, neighbors[i0]);
+          if (!c3t3.is_in_complex(vh1))
+            neighbors[i1] = (std::max)(0, neighbors[i1]);
+
+          if (!c3t3.is_in_complex(vh0) && on_feature_v1)
+          {
+            const Point_3& p1 = point(vh1->point());
+            smoothed_positions[i0] = smoothed_positions[i0] + Vector_3(p1.x(), p1.y(), p1.z());
+            neighbors[i0]++;
+          }
+          if (!c3t3.is_in_complex(vh1) && on_feature_v0)
+          {
+            const Point_3& p0 = point(vh0->point());
+            smoothed_positions[i1] = smoothed_positions[i1] + Vector_3(p0.x(), p0.y(), p0.z());
+            neighbors[i1]++;
+          }
+        }
+      }
+
+      // Smooth
+      for (Vertex_handle v : tr.finite_vertex_handles())
+      {
+        const std::size_t& vid = vertex_id.at(v);
+        if (neighbors[vid] > 1)
+        {
+          Vector_3 smoothed_position = smoothed_positions[vid] / neighbors[vid];
+          Vector_3 final_position = CGAL::NULL_VECTOR;
+
+          std::size_t count = 0;
+          const Vector_3 current_pos(CGAL::ORIGIN, point(v->point()));
+
+          const std::vector<Surface_patch_index>& v_surface_indices = vertices_surface_indices[v];
+          for (const Surface_patch_index& si : v_surface_indices)
+          {
+            Vector_3 normal_projection
+              = project_on_tangent_plane(smoothed_position, current_pos, vertices_normals[v][si]);
+
+            //Check if the mls surface exists to avoid degenerated cases
+            if (boost::optional<Vector_3> mls_projection = project(si, normal_projection)) {
+              final_position = final_position + *mls_projection;
+            }
+            else {
+              final_position = final_position + normal_projection;
+            }
+            count++;
+          }
+
+          if (count > 0)
+            final_position = final_position / static_cast<FT>(count);
+          else
+            final_position = smoothed_position;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+          os_surf << "2 " << current_pos << " " << final_position << std::endl,
+#endif
+                  // move vertex
+                  v->set_point(typename Tr::Point(
+                                 final_position.x(), final_position.y(), final_position.z()));
+        }
+        else if (neighbors[vid] > 0)
+        {
+          Vector_3 final_position = CGAL::NULL_VECTOR;
+
+          int count = 0;
+          const Vector_3 current_pos(CGAL::ORIGIN, point(v->point()));
+
+          const std::vector<Surface_patch_index>& v_surface_indices = vertices_surface_indices[v];
+          for (const Surface_patch_index si : v_surface_indices)
+          {
+            //Check if the mls surface exists to avoid degenerated cases
+
+            if (boost::optional<Vector_3> mls_projection = project(si, current_pos)) {
+              final_position = final_position + *mls_projection;
+            }
+            else {
+              final_position = final_position + current_pos;
+            }
+            count++;
+          }
+
+          if (count > 0)
+            final_position = final_position / static_cast<FT>(count);
+          else
+            final_position = current_pos;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+          os_surf << "2 " << current_pos << " " << final_position << std::endl,
+#endif
+                  // move vertex
+                  v->set_point(
+                    typename Tr::Point(final_position.x(), final_position.y(), final_position.z()));
+        }
+      }
+#endif //CGAL_TETRAHEDRAL_REMESHING_SMOOTH_SHARP_EDGES
+
+      smoothed_positions.assign(nbv, CGAL::NULL_VECTOR);
+      neighbors.assign(nbv, -1);
+
+      /////////////// EDGES ON SURFACE, BUT NOT IN COMPLEX //////////////////
+      for (const Edge& e : tr.finite_edges())
+      {
+        if (is_boundary(c3t3, e, cell_selector) && !c3t3.is_in_complex(e))
+        {
+          const Vertex_handle vh0 = e.first->vertex(e.second);
+          const Vertex_handle vh1 = e.first->vertex(e.third);
+
+          const std::size_t& i0 = vertex_id.at(vh0);
+          const std::size_t& i1 = vertex_id.at(vh1);
+
+          const bool on_feature_v0 = is_on_feature(vh0);
+          const bool on_feature_v1 = is_on_feature(vh1);
+
+          if (!on_feature_v0)
+            neighbors[i0] = (std::max)(0, neighbors[i0]);
+          if (!on_feature_v1)
+            neighbors[i1] = (std::max)(0, neighbors[i1]);
+
+          if (!on_feature_v0)
+          {
+            const Point_3& p1 = point(vh1->point());
+            smoothed_positions[i0] = smoothed_positions[i0] + Vector_3(p1.x(), p1.y(), p1.z());
+            neighbors[i0]++;
+          }
+          if (!on_feature_v1)
+          {
+            const Point_3& p0 = point(vh0->point());
+            smoothed_positions[i1] = smoothed_positions[i1] + Vector_3(p0.x(), p0.y(), p0.z());
+            neighbors[i1]++;
+          }
+        }
+      }
+
+      for (Vertex_handle v : tr.finite_vertex_handles())
+      {
+        if (v->in_dimension() != 2)
+          continue;
+
+        const std::size_t& vid = vertex_id.at(v);
+        if (neighbors[vid] > 1)
+        {
+          Vector_3 smoothed_position = smoothed_positions[vid] / static_cast<FT>(neighbors[vid]);
+          const Vector_3 current_pos(CGAL::ORIGIN, point(v->point()));
+          Vector_3 final_position = CGAL::NULL_VECTOR;
+
+          const Surface_patch_index si = surface_patch_index(v, c3t3);
+          CGAL_assertion(si != Surface_patch_index());
+
+          Vector_3 normal_projection = project_on_tangent_plane(smoothed_position,
+                                       current_pos,
+                                       vertices_normals[v][si]);
+
+          if (boost::optional<Vector_3> mls_projection = project(si, normal_projection))
+            final_position = final_position + *mls_projection;
+          else
+            final_position = smoothed_position;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+          os_surf << "2 " << current_pos << " " << final_position << std::endl,
+#endif
+                  check_inversion_and_move(v, typename Tr::Point(
+                                             final_position.x(), final_position.y(), final_position.z()),
+                                           inc_cells[vid],
+                                           tr);
+        }
+        else if (neighbors[vid] > 0)
+        {
+          const Surface_patch_index si = surface_patch_index(v, c3t3);
+          CGAL_assertion(si != Surface_patch_index());
+
+          const Vector_3 current_pos(CGAL::ORIGIN, point(v->point()));
+
+          if (boost::optional<Vector_3> mls_projection = project(si, current_pos))
+          {
+            const typename Tr::Point new_pos(CGAL::ORIGIN + *mls_projection);
+            check_inversion_and_move(v, new_pos, inc_cells[vid], tr);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+            os_surf0 << "2 " << current_pos << " " << new_pos << std::endl;
+#endif
+          }
+        }
+      }
+    }
+    CGAL_assertion(CGAL::Tetrahedral_remeshing::debug::are_cell_orientations_valid(tr));
+    ////   end if(!protect_boundaries)
+
+    smoothed_positions.assign(nbv, CGAL::NULL_VECTOR);
+    neighbors.assign(nbv, 0/*for dim 3 vertices, start counting directly from 0*/);
+
+    ////////////// INTERNAL VERTICES ///////////////////////
+    for (const Edge& e : tr.finite_edges())
+    {
+      if (!is_outside(e, c3t3, cell_selector))
+      {
+        const Vertex_handle vh0 = e.first->vertex(e.second);
+        const Vertex_handle vh1 = e.first->vertex(e.third);
+
+        const std::size_t& i0 = vertex_id.at(vh0);
+        const std::size_t& i1 = vertex_id.at(vh1);
+
+        if (c3t3.in_dimension(vh0) == 3)
+        {
+          const Point_3& p1 = point(vh1->point());
+          smoothed_positions[i0] = smoothed_positions[i0] + Vector_3(CGAL::ORIGIN, p1);
+          neighbors[i0]++;
+        }
+        if (c3t3.in_dimension(vh1) == 3)
+        {
+          const Point_3& p0 = point(vh0->point());
+          smoothed_positions[i1] = smoothed_positions[i1] + Vector_3(CGAL::ORIGIN, p0);
+          neighbors[i1]++;
+        }
+      }
+    }
+
+    for (Vertex_handle v : tr.finite_vertex_handles())
+    {
+      const std::size_t& vid = vertex_id.at(v);
+      if (c3t3.in_dimension(v) == 3 && neighbors[vid] > 1)
+      {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+        ++nb_done;
+#endif
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        os_vol << "2 " << point(v->point());
+#endif
+        const Vector_3 p = smoothed_positions[vid] / static_cast<FT>(neighbors[vid]);
+        check_inversion_and_move(v, typename Tr::Point(p.x(), p.y(), p.z()), inc_cells[vid], tr);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        os_vol << " " << point(v->point()) << std::endl;
+#endif
+      }
+    }
+    CGAL_assertion(CGAL::Tetrahedral_remeshing::debug::are_cell_orientations_valid(tr));
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+    std::cout << " done (" << nb_done << " vertices smoothed)." << std::endl;
+#endif
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    CGAL::Tetrahedral_remeshing::debug::dump_vertices_by_dimension(
+      c3t3.triangulation(), "c3t3_vertices_after_smoothing");
+    os_surf.close();
+    os_vol.close();
+#endif
+  }
+
+};//end class Tetrahedral_remeshing_smoother
+}//namespace internal
+}//namespace Tetrahedral_adaptive_remeshing
+}//namespace CGAL
+
+#endif //CGAL_INTERNAL_SMOOTH_VERTICES_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h
new file mode 100644
index 00000000000..f75c940d080
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/split_long_edges.h
@@ -0,0 +1,333 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_INTERNAL_SPLIT_LONG_EDGES_H
+#define CGAL_INTERNAL_SPLIT_LONG_EDGES_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <boost/bimap.hpp>
+#include <boost/bimap/set_of.hpp>
+#include <boost/bimap/multiset_of.hpp>
+#include <boost/unordered_map.hpp>
+#include <boost/container/small_vector.hpp>
+
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+
+#include <functional>
+#include <utility>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+template<typename C3t3>
+typename C3t3::Vertex_handle split_edge(const typename C3t3::Edge& e,
+                                        C3t3& c3t3)
+{
+  typedef typename C3t3::Triangulation       Tr;
+  typedef typename C3t3::Subdomain_index     Subdomain_index;
+  typedef typename C3t3::Surface_patch_index Surface_patch_index;
+  typedef typename Tr::Geom_traits::Point_3 Point;
+  typedef typename Tr::Facet                Facet;
+  typedef typename Tr::Vertex_handle        Vertex_handle;
+  typedef typename Tr::Cell_handle          Cell_handle;
+  typedef typename Tr::Cell_circulator      Cell_circulator;
+
+  Tr& tr = c3t3.triangulation();
+  const Vertex_handle v1 = e.first->vertex(e.second);
+  const Vertex_handle v2 = e.first->vertex(e.third);
+
+  const Point m = tr.geom_traits().construct_midpoint_3_object()
+    (point(v1->point()), point(v2->point()));
+
+  //backup subdomain info of incident cells before making changes
+  short dimension = (c3t3.is_in_complex(e)) ? 1 : 3;
+  boost::unordered_map<Facet, Subdomain_index> cells_info;
+  boost::unordered_map<Facet, std::pair<Vertex_handle, Surface_patch_index> > facets_info;
+
+  // check orientation and collect incident cells to avoid circulating twice
+  boost::container::small_vector<Cell_handle, 30> inc_cells;
+  Cell_circulator circ = tr.incident_cells(e);
+  Cell_circulator end = circ;
+  do
+  {
+    inc_cells.push_back(circ);
+    if (tr.is_infinite(circ))
+    {
+      ++circ;
+      continue;
+    }
+
+    //1st half-cell
+    std::array<Point, 4> pts = { point(circ->vertex(0)->point()),
+                                 point(circ->vertex(1)->point()),
+                                 point(circ->vertex(2)->point()),
+                                 point(circ->vertex(3)->point()) };
+    const int i1 = circ->index(v1);
+    const Point p1 = pts[i1];
+    pts[i1] = m;
+    if(CGAL::orientation(pts[0], pts[1], pts[2], pts[3]) != CGAL::POSITIVE)
+      return Vertex_handle();
+
+    //2nd half-cell
+    pts[i1] = p1;
+    pts[circ->index(v2)] = m;
+    if (CGAL::orientation(pts[0], pts[1], pts[2], pts[3]) != CGAL::POSITIVE)
+      return Vertex_handle();
+
+    ++circ;
+  }
+  while (circ != end);
+
+  for(Cell_handle c : inc_cells)
+  {
+    const int index_v1 = c->index(v1);
+    const int index_v2 = c->index(v2);
+
+    //keys are the opposite facets to the ones not containing e,
+    //because they will not be modified
+    const Subdomain_index subdomain = c3t3.subdomain_index(c);
+    const Facet opp_facet1 = tr.mirror_facet(Facet(c, index_v1));
+    const Facet opp_facet2 = tr.mirror_facet(Facet(c, index_v2));
+
+    // volume data
+    cells_info.insert(std::make_pair(opp_facet1, subdomain));
+    cells_info.insert(std::make_pair(opp_facet2, subdomain));
+    if (c3t3.is_in_complex(c))
+      c3t3.remove_from_complex(c);
+
+    // surface data for facets of the cells to be split
+    const int findex = CGAL::Triangulation_utils_3::next_around_edge(index_v1, index_v2);
+    if (c3t3.is_in_complex(c, findex))
+    {
+      if (dimension == 3)
+        dimension = 2;
+    }
+    Surface_patch_index patch = c3t3.surface_patch_index(c, findex);
+    Vertex_handle opp_vertex = c->vertex(findex);
+    facets_info.insert(std::make_pair(opp_facet1,
+                                      std::make_pair(opp_vertex, patch)));
+    facets_info.insert(std::make_pair(opp_facet2,
+                                      std::make_pair(opp_vertex, patch)));
+
+    if(c3t3.is_in_complex(c, findex))
+      c3t3.remove_from_complex(c, findex);
+  }
+
+  // insert midpoint
+  Vertex_handle new_v = tr.tds().insert_in_edge(e);
+  new_v->set_point(typename Tr::Point(m));
+  new_v->set_dimension(dimension);
+
+  // update c3t3 with subdomain and surface patch indices
+  std::vector<Cell_handle> new_cells;
+  tr.incident_cells(new_v, std::back_inserter(new_cells));
+  for (Cell_handle new_cell : new_cells)
+  {
+    const Facet fi(new_cell, new_cell->index(new_v));
+    const Facet mfi = tr.mirror_facet(fi);
+
+    //get subdomain info back
+    CGAL_assertion(cells_info.find(mfi) != cells_info.end());
+    Subdomain_index n_index = cells_info.at(mfi);
+    if (Subdomain_index() != n_index)
+      c3t3.add_to_complex(new_cell, n_index);
+    else
+      new_cell->set_subdomain_index(Subdomain_index());
+
+    // get surface info back
+    CGAL_assertion(facets_info.find(mfi) != facets_info.end());
+    const std::pair<Vertex_handle, Surface_patch_index> v_and_opp_patch = facets_info.at(mfi);
+
+    // facet opposite to new_v (status wrt c3t3 is unchanged)
+    new_cell->set_surface_patch_index(new_cell->index(new_v),
+                                      mfi.first->surface_patch_index(mfi.second));
+
+    // new half-facet (added or not to c3t3 depending on the stored surface patch index)
+    if (Surface_patch_index() == v_and_opp_patch.second)
+      new_cell->set_surface_patch_index(new_cell->index(v_and_opp_patch.first),
+                                        Surface_patch_index());
+    else
+      c3t3.add_to_complex(new_cell,
+                          new_cell->index(v_and_opp_patch.first),
+                          v_and_opp_patch.second);
+
+    // newly created internal facet
+    for (int i = 0; i < 4; ++i)
+    {
+      const Vertex_handle vi = new_cell->vertex(i);
+      if (vi == v1 || vi == v2)
+      {
+        new_cell->set_surface_patch_index(i, Surface_patch_index());
+        break;
+      }
+    }
+
+    //the 4th facet (new_v, v_and_opp_patch.first, v1 or v2)
+    // will have its patch tagged from the other side, if needed
+  }
+
+  return new_v;
+}
+
+template<typename C3T3, typename CellSelector>
+bool can_be_split(const typename C3T3::Edge& e,
+                  const C3T3& c3t3,
+                  const bool protect_boundaries,
+                  CellSelector cell_selector)
+{
+  if (is_outside(e, c3t3, cell_selector))
+    return false;
+
+  if (protect_boundaries)
+  {
+    if (c3t3.is_in_complex(e))
+      return false;
+    else if (is_boundary(c3t3, e, cell_selector))
+      return false;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    if (!is_internal(e, c3t3, cell_selector))
+    {
+      std::cerr << "e is not inside!?" << std::endl;
+      typename C3T3::Vertex_handle v1 = e.first->vertex(e.second);
+      typename C3T3::Vertex_handle v2 = e.first->vertex(e.third);
+      std::cerr << v1->point() << " " << v2->point() << std::endl;
+    }
+#endif
+
+    CGAL_assertion(is_internal(e, c3t3, cell_selector));
+    return true;
+  }
+  else
+  {
+    return true;
+  }
+}
+
+template<typename C3T3, typename CellSelector, typename Visitor>
+void split_long_edges(C3T3& c3t3,
+                      const typename C3T3::Triangulation::Geom_traits::FT& high,
+                      const bool protect_boundaries,
+                      CellSelector cell_selector,
+                      Visitor& visitor)
+{
+  typedef typename C3T3::Triangulation       T3;
+  typedef typename T3::Cell_handle           Cell_handle;
+  typedef typename T3::Edge                  Edge;
+  typedef typename T3::Finite_edges_iterator Finite_edges_iterator;
+  typedef typename T3::Vertex_handle         Vertex_handle;
+  typedef typename std::pair<Vertex_handle, Vertex_handle> Edge_vv;
+
+  typedef typename T3::Geom_traits     Gt;
+  typedef typename T3::Geom_traits::FT FT;
+  typedef boost::bimap<
+  boost::bimaps::set_of<Edge_vv>,
+        boost::bimaps::multiset_of<FT, std::greater<FT> > >  Boost_bimap;
+  typedef typename Boost_bimap::value_type               long_edge;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "Split long edges (" << high << ")...";
+  std::cout.flush();
+  std::size_t nb_splits = 0;
+#endif
+  const FT sq_high = high*high;
+
+  //collect long edges
+  T3& tr = c3t3.triangulation();
+  Boost_bimap long_edges;
+  for (Finite_edges_iterator eit = tr.finite_edges_begin();
+       eit != tr.finite_edges_end(); ++eit)
+  {
+    Edge e = *eit;
+    if (!can_be_split(e, c3t3, protect_boundaries, cell_selector))
+      continue;
+
+    typename Gt::Compute_squared_length_3 sql
+      = tr.geom_traits().compute_squared_length_3_object();
+    FT sqlen = sql(tr.segment(e));
+    if (sqlen > sq_high)
+      long_edges.insert(long_edge(make_vertex_pair<T3>(e), sqlen));
+  }
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  debug::dump_edges(long_edges, "long_edges.polylines.txt");
+
+  std::ofstream ofs("midpoints.off");
+  ofs << "OFF" << std::endl;
+  ofs << long_edges.size() << " 0 0" << std::endl;
+#endif
+  while(!long_edges.empty())
+  {
+    //the edge with longest length
+    typename Boost_bimap::right_map::iterator eit = long_edges.right.begin();
+    Edge_vv e = eit->second;
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS
+    const double sqlen = eit->first;
+#endif
+    long_edges.right.erase(eit);
+
+    Cell_handle cell;
+    int i1, i2;
+    if ( tr.tds().is_edge(e.first, e.second, cell, i1, i2))
+    {
+      Edge edge(cell, i1, i2);
+
+      //check that splittability has not changed
+      if (!can_be_split(edge, c3t3, protect_boundaries, cell_selector))
+        continue;
+
+      visitor.before_split(tr, edge);
+      Vertex_handle vh = split_edge(edge, c3t3);
+
+      if(vh != Vertex_handle())
+        visitor.after_split(tr, vh);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+      if (vh != Vertex_handle())
+        ofs << vh->point() << std::endl;
+#endif
+
+#if  defined(CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS) \
+|| defined(CGAL_TETRAHEDRAL_REMESHING_VERBOSE)
+      if (vh != Vertex_handle())
+        ++nb_splits;
+#endif
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS
+      std::cout << "\rSplit (" << high << ")... ("
+                << long_edges.left.size() << " long edges, "
+                << "length  = " << std::sqrt(sqlen) << ", "
+                << nb_splits << " splits)";
+      std::cout.flush();
+#endif
+    }
+  }//end loop on long_edges
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  if(ofs.is_open())
+    ofs.close();
+#endif
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << " done (" << nb_splits << " splits)." << std::endl;
+#endif
+}
+
+} // internal
+} // Tetrahedral_remeshing
+} // CGAL
+
+#endif // CGAL_INTERNAL_SPLIT_LONG_EDGES_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h
new file mode 100644
index 00000000000..fb4234781ee
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h
@@ -0,0 +1,554 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef TETRAHEDRAL_REMESHING_IMPL_H
+#define TETRAHEDRAL_REMESHING_IMPL_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE_PROGRESS
+#define CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+#endif
+
+#include <CGAL/Mesh_complex_3_in_triangulation_3.h>
+#include <CGAL/Triangulation_utils_3.h>
+
+#include <CGAL/Tetrahedral_remeshing/internal/split_long_edges.h>
+#include <CGAL/Tetrahedral_remeshing/internal/collapse_short_edges.h>
+#include <CGAL/Tetrahedral_remeshing/internal/flip_edges.h>
+#include <CGAL/Tetrahedral_remeshing/internal/smooth_vertices.h>
+
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h>
+#include <CGAL/Tetrahedral_remeshing/internal/compute_c3t3_statistics.h>
+
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+namespace internal
+{
+class Default_remeshing_visitor
+{
+public:
+  template<typename Tr>
+  void before_split(const Tr& /* tr */, const typename Tr::Edge& /* e */) {}
+  template<typename Tr>
+  void after_split(const Tr& /* tr */, const typename Tr::Vertex_handle /* new_v */) {}
+
+  template<typename CellHandleOld, typename CellHandleNew>
+  void after_add_cell(CellHandleOld /* co */, CellHandleNew /* cn */) const {}
+
+  template<typename CellHandle>
+  void before_flip(const CellHandle /* c */) {}
+  template<typename CellHandle>
+  void after_flip(CellHandle /* c */) {}
+};
+
+template<typename Tr>
+struct All_cells_selected
+{
+  typedef typename Tr::Cell_handle argument_type;
+  typedef typename Tr::Cell::Subdomain_index Subdomain_index;
+
+  typedef bool                     result_type;
+
+  result_type operator()(const argument_type c) const
+  {
+    return c->subdomain_index() != Subdomain_index();
+  }
+};
+
+template<typename Primitive>
+struct No_constraint_pmap
+{
+public:
+  typedef Primitive                           key_type;
+  typedef bool                                value_type;
+  typedef value_type&                         reference;
+  typedef boost::read_write_property_map_tag  category;
+
+  friend bool get(const No_constraint_pmap&, const key_type&) {
+    return false;
+  }
+  friend void put(No_constraint_pmap&, const key_type&, const bool) {}
+};
+
+template<typename Triangulation
+         , typename SizingFunction
+         , typename EdgeIsConstrainedMap
+         , typename FacetIsConstrainedMap
+         , typename CellSelector
+         , typename Visitor
+         , typename CornerIndex = int
+         , typename CurveIndex = int
+         >
+class Adaptive_remesher
+{
+  typedef Triangulation Tr;
+  typedef typename Tr::Geom_traits::FT FT;
+
+  typedef CGAL::Mesh_complex_3_in_triangulation_3<Tr, CornerIndex, CurveIndex> C3t3;
+
+  typedef typename C3t3::Cell_handle         Cell_handle;
+  typedef typename C3t3::Vertex_handle       Vertex_handle;
+  typedef typename C3t3::Subdomain_index     Subdomain_index;
+  typedef typename C3t3::Surface_patch_index Surface_patch_index;
+
+  typedef Tetrahedral_remeshing_smoother<C3t3> Smoother;
+
+private:
+  C3t3 m_c3t3;
+  const SizingFunction& m_sizing;
+  const bool m_protect_boundaries;
+  CellSelector m_cell_selector;
+  Visitor& m_visitor;
+  Smoother m_vertex_smoother;//initialized with initial surface
+
+  C3t3* m_c3t3_pbackup;
+  Triangulation* m_tr_pbackup; //backup to re-swap triangulations when done
+
+public:
+  Adaptive_remesher(Triangulation& tr
+                    , const SizingFunction& sizing
+                    , const bool protect_boundaries
+                    , EdgeIsConstrainedMap ecmap
+                    , FacetIsConstrainedMap fcmap
+                    , CellSelector cell_selector
+                    , Visitor& visitor
+                   )
+    : m_c3t3()
+    , m_sizing(sizing)
+    , m_protect_boundaries(protect_boundaries)
+    , m_cell_selector(cell_selector)
+    , m_visitor(visitor)
+    , m_c3t3_pbackup(NULL)
+    , m_tr_pbackup(&tr)
+  {
+    m_c3t3.triangulation().swap(tr);
+
+    init_c3t3(ecmap, fcmap);
+    m_vertex_smoother.init(m_c3t3, m_cell_selector);
+
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "00-init");
+#endif
+  }
+
+  Adaptive_remesher(C3t3& c3t3
+                    , const SizingFunction& sizing
+                    , const bool protect_boundaries
+                    , EdgeIsConstrainedMap ecmap
+                    , FacetIsConstrainedMap fcmap
+                    , CellSelector cell_selector
+                    , Visitor& visitor
+                   )
+    : m_c3t3()
+    , m_sizing(sizing)
+    , m_protect_boundaries(protect_boundaries)
+    , m_cell_selector(cell_selector)
+    , m_visitor(visitor)
+    , m_c3t3_pbackup(&c3t3)
+    , m_tr_pbackup(NULL)
+  {
+    m_c3t3.swap(c3t3);
+
+    init_c3t3(ecmap, fcmap);
+    m_vertex_smoother.init(m_c3t3, m_cell_selector);
+
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "00-init");
+#endif
+  }
+
+  bool input_is_c3t3() const
+  {
+    return m_c3t3_pbackup != NULL;
+  }
+
+  void split()
+  {
+    CGAL_assertion(check_vertex_dimensions());
+
+    const FT target_edge_length = m_sizing(CGAL::ORIGIN);
+    const FT emax = FT(4)/FT(3) * target_edge_length;
+    split_long_edges(m_c3t3, emax, m_protect_boundaries,
+                     m_cell_selector, m_visitor);
+
+    CGAL_assertion(tr().tds().is_valid(true));
+    CGAL_assertion(debug::are_cell_orientations_valid(tr()));
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "1-split");
+#endif
+  }
+
+  void collapse()
+  {
+    CGAL_assertion(check_vertex_dimensions());
+
+    const FT target_edge_length = m_sizing(CGAL::ORIGIN);
+    FT emin = FT(4)/FT(5) * target_edge_length;
+    FT emax = FT(4)/FT(3) * target_edge_length;
+    collapse_short_edges(m_c3t3, emin, emax, m_protect_boundaries,
+                         m_cell_selector, m_visitor);
+
+    CGAL_assertion(tr().tds().is_valid(true));
+    CGAL_assertion(debug::are_cell_orientations_valid(tr()));
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "2-collapse");
+#endif
+  }
+
+  void flip()
+  {
+    flip_edges(m_c3t3, m_protect_boundaries,
+               m_cell_selector, m_visitor);
+
+    CGAL_assertion(tr().tds().is_valid(true));
+    CGAL_assertion(debug::are_cell_orientations_valid(tr()));
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "3-flip");
+#endif
+  }
+
+  void smooth()
+  {
+    m_vertex_smoother.smooth_vertices(m_c3t3, m_protect_boundaries, m_cell_selector);
+
+    CGAL_assertion(tr().tds().is_valid(true));
+    CGAL_assertion(debug::are_cell_orientations_valid(tr()));
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "4-smooth");
+#endif
+  }
+
+  bool resolution_reached()
+  {
+    const FT target_edge_length = m_sizing(CGAL::ORIGIN);
+
+    FT emax = FT(4) / FT(3) * target_edge_length;
+    FT emin = FT(4) / FT(5) * target_edge_length;
+
+    FT sqmax = emax * emax;
+    FT sqmin = emin * emin;
+
+    typedef typename Tr::Edge Edge;
+    for (Edge e : tr().finite_edges())
+    {
+      // skip protected edges
+      if (m_protect_boundaries)
+      {
+        if(  m_c3t3.is_in_complex(e)
+             || is_boundary(m_c3t3, e, m_cell_selector))
+          continue;
+      }
+
+      FT sqlen = tr().segment(e).squared_length();
+      if (sqlen < sqmin || sqlen > sqmax)
+        return false;
+    }
+    std::cout << "Resolution reached" << std::endl;
+    return true;
+  }
+
+  //peel off slivers
+  std::size_t postprocess(const double sliver_angle = 0.1)
+  {
+    if (m_protect_boundaries)
+      return 0;
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+    std::cout << "Postprocess...";
+    std::cout.flush();
+#endif
+
+    std::size_t nb_slivers_peel = 0;
+    for (Cell_handle cit : tr().finite_cell_handles())
+    {
+      if(m_c3t3.is_in_complex(cit) && min_dihedral_angle(tr(), cit) < sliver_angle)
+      {
+        for (int i = 0; i < 4; ++i)
+        {
+          if (!m_c3t3.is_in_complex(cit->neighbor(i)))
+          {
+            m_c3t3.remove_from_complex(cit);
+            ++nb_slivers_peel;
+          }
+        }
+      }
+    }
+
+    CGAL_assertion(tr().tds().is_valid(true));
+    CGAL_assertion(debug::are_cell_orientations_valid(tr()));
+
+#ifdef CGAL_DUMP_REMESHING_STEPS
+    CGAL::Tetrahedral_remeshing::debug::dump_c3t3(m_c3t3, "99-postprocess");
+#endif
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+    std::cout << "(peeling removed " << nb_slivers_peel << " slivers)" << std::endl;
+    std::cout << "done." << std::endl;
+#endif
+    return nb_slivers_peel;
+  }
+
+  void finalize()
+  {
+    if (m_c3t3_pbackup != NULL)
+      m_c3t3_pbackup->swap(m_c3t3);
+    else
+      m_tr_pbackup->swap(m_c3t3.triangulation());
+  }
+
+private:
+  void init_c3t3(const EdgeIsConstrainedMap& ecmap,
+                 const FacetIsConstrainedMap& fcmap)
+  {
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    std::size_t nbc = 0;
+    std::size_t nbf = 0;
+    std::size_t nbe = 0;
+    std::size_t nbv = 0;
+#endif
+    //tag cells
+    for (Cell_handle cit : tr().finite_cell_handles())
+    {
+      if (m_cell_selector(cit))
+      {
+        const Subdomain_index index = cit->subdomain_index();
+        if(!input_is_c3t3())
+          m_c3t3.remove_from_complex(cit);
+        m_c3t3.add_to_complex(cit, index);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        ++nbc;
+#endif
+      }
+      if (!input_is_c3t3())
+      {
+        for (int i = 0; i < 4; ++i)
+        {
+          if (cit->vertex(i)->in_dimension() == -1)
+            cit->vertex(i)->set_dimension(3);
+        }
+      }
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+      else if (input_is_c3t3() && m_c3t3.is_in_complex(cit))
+        ++nbc;
+#endif
+    }
+
+    //tag facets
+    typedef typename Tr::Facet Facet;
+    for (const Facet& f : tr().finite_facets())
+    {
+      const Facet mf = tr().mirror_facet(f);
+      const Subdomain_index s1 = f.first->subdomain_index();
+      const Subdomain_index s2 = mf.first->subdomain_index();
+      if (s1 != s2
+          || get(fcmap, f)
+          || get(fcmap, mf)
+          || (m_c3t3_pbackup == NULL && f.first->is_facet_on_surface(f.second)))
+      {
+        Surface_patch_index patch = f.first->surface_patch_index(f.second);
+        if(patch == Surface_patch_index())
+          set_surface_patch_index_to_default(s1, s2, patch);
+        m_c3t3.add_to_complex(f, patch);
+
+        const int i = f.second;
+        for (int j = 0; j < 3; ++j)
+        {
+          Vertex_handle vij = f.first->vertex(Tr::vertex_triple_index(i, j));
+          if (vij->in_dimension() == -1 || vij->in_dimension() > 2)
+            vij->set_dimension(2);
+        }
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        ++nbf;
+#endif
+      }
+    }
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    CGAL::Tetrahedral_remeshing::debug::dump_facets_in_complex(m_c3t3, "facets_in_complex.off");
+#endif
+
+    //tag edges
+    typedef typename Tr::Edge Edge;
+    for (const Edge& e : tr().finite_edges())
+    {
+      if (m_c3t3.is_in_complex(e))
+      {
+        CGAL_assertion(m_c3t3.in_dimension(e.first->vertex(e.second)) <= 1);
+        CGAL_assertion(m_c3t3.in_dimension(e.first->vertex(e.third)) <= 1);
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        ++nbe;
+#endif
+        continue;
+      }
+
+      if (get(ecmap, CGAL::Tetrahedral_remeshing::make_vertex_pair<Tr>(e))
+          || nb_incident_subdomains(e, m_c3t3) > 2
+          || nb_incident_surface_patches(e, m_c3t3) > 1)
+      {
+        m_c3t3.add_to_complex(e, 1);
+
+        Vertex_handle v = e.first->vertex(e.second);
+        if (v->in_dimension() == -1 || v->in_dimension() > 1)
+          v->set_dimension(1);
+
+        v = e.first->vertex(e.third);
+        if (v->in_dimension() == -1 || v->in_dimension() > 1)
+          v->set_dimension(1);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        ++nbe;
+#endif
+      }
+    }
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    CGAL::Tetrahedral_remeshing::debug::dump_edges_in_complex(m_c3t3, "edges_in_complex.polylines.txt");
+#endif
+
+    //tag vertices
+    unsigned int corner_id = 0;
+    for (Vertex_handle vit : tr().finite_vertex_handles())
+    {
+      if ( vit->in_dimension() == 0
+           || nb_incident_complex_edges(vit, m_c3t3) > 2)
+      {
+        if(!m_c3t3.is_in_complex(vit))
+          m_c3t3.add_to_complex(vit, ++corner_id);
+
+        if (vit->in_dimension() == -1 || vit->in_dimension() > 0)
+          vit->set_dimension(0);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+        ++nbv;
+#endif
+      }
+    }
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+    std::cout << "C3t3 ready :" << std::endl;
+    std::cout << "\t cells    = " << nbc << std::endl;
+    std::cout << "\t facets   = " << nbf << std::endl;
+    std::cout << "\t edges    = " << nbe << std::endl;
+    std::cout << "\t vertices = " << nbv << std::endl;
+
+    CGAL::Tetrahedral_remeshing::debug::dump_vertices_by_dimension(
+      m_c3t3.triangulation(), "c3t3_vertices_");
+#endif
+  }
+
+private:
+  bool check_vertex_dimensions()
+  {
+    for (Vertex_handle vit : tr().finite_vertex_handles())
+    {
+      // dimension is -1 for Mesh_3 "far points"
+      // for other vertices, it is in [0; 3]
+      if (vit->in_dimension() < -1 || vit->in_dimension() > 3)
+        return false;
+    }
+    return true;
+  }
+
+  template<typename PatchIndex>
+  void set_surface_patch_index_to_default(const Subdomain_index&,
+                                          const Subdomain_index&,
+                                          PatchIndex& patch)
+  {
+    if(m_c3t3.number_of_facets() == 0)
+      patch = 1;
+    else
+      patch = m_c3t3.surface_patch_index(*m_c3t3.facets_in_complex_begin());
+  }
+
+  void set_surface_patch_index_to_default(const Subdomain_index& s1,
+                                          const Subdomain_index& s2,
+                                          std::pair<Subdomain_index, Subdomain_index>& patch)
+  {
+    patch = (s1 < s2) ? std::make_pair(s1, s2) : std::make_pair(s2, s1);
+  }
+
+public:
+  Tr& tr()
+  {
+    return m_c3t3.triangulation();
+  }
+  const Tr& tr() const
+  {
+    return m_c3t3.triangulation();
+  }
+
+  void remesh(const std::size_t& max_it,
+              const std::size_t& nb_extra_iterations)
+  {
+    std::size_t it_nb = 0;
+    while (it_nb < max_it)
+    {
+      ++it_nb;
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+      std::cout << "# Iteration " << it_nb << " #" << std::endl;
+#endif
+      if (!resolution_reached())
+      {
+        split();
+        collapse();
+      }
+      flip();
+      smooth();
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+      std::cout << "# Iteration " << it_nb << " done : "
+                << tr().number_of_vertices()
+                << " vertices #" << std::endl;
+#endif
+#ifdef CGAL_DUMP_REMESHING_STEPS
+      std::ostringstream ossi;
+      ossi << "statistics_" << it_nb << ".txt";
+      Tetrahedral_remeshing::internal::compute_statistics(
+        tr(), m_cell_selector, ossi.str().c_str());
+#endif
+    }
+
+    while (it_nb < max_it + nb_extra_iterations)
+    {
+      ++it_nb;
+
+      flip();
+      smooth();
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+      std::cout << "# Iteration " << it_nb << " (flip and smooth only) done : "
+                << tr().number_of_vertices()
+                << " vertices #" << std::endl;
+#endif
+#ifdef CGAL_DUMP_REMESHING_STEPS
+      std::ostringstream ossi;
+      ossi << "statistics_" << it_nb << ".txt";
+      Tetrahedral_remeshing::internal::compute_statistics(
+        tr(),  m_cell_selector, ossi.str().c_str());
+#endif
+    }
+
+    postprocess(); //peel off boundary slivers
+
+    finalize();
+    //Warning : triangulation() is now empty
+  }
+
+};//end class Adaptive_remesher
+
+}//end namespace internal
+}//end namespace Tetrahedral_remeshing
+}//end namespace CGAL
+
+#endif //TETRAHEDRAL_REMESHING_IMPL_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h
new file mode 100644
index 00000000000..d8e18c6d8fe
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/internal/tetrahedral_remeshing_helpers.h
@@ -0,0 +1,1418 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef CGAL_INTERNAL_TET_REMESHING_HELPERS_H
+#define CGAL_INTERNAL_TET_REMESHING_HELPERS_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <utility>
+#include <array>
+
+#include <CGAL/Point_3.h>
+#include <CGAL/Weighted_point_3.h>
+#include <CGAL/Vector_3.h>
+#include <CGAL/utility.h>
+
+#include <CGAL/IO/File_binary_mesh_3.h>
+
+namespace CGAL
+{
+namespace Tetrahedral_remeshing
+{
+
+enum Subdomain_relation { EQUAL, DIFFERENT, INCLUDED, INCLUDES };
+enum Sliver_removal_result { INVALID_ORIENTATION, INVALID_CELL, INVALID_VERTEX,
+  NOT_FLIPPABLE, EDGE_PROBLEM, VALID_FLIP, NO_BEST_CONFIGURATION, EXISTING_EDGE };
+
+template<typename K>
+CGAL::Point_3<K> point(const CGAL::Point_3<K>& p)
+{
+  return p;
+}
+template<typename K>
+CGAL::Point_3<K> point(const CGAL::Weighted_point_3<K>& wp)
+{
+  typename K::Construct_point_3 pt = K().construct_point_3_object();
+  return pt(wp);
+}
+
+template <typename K>
+CGAL::Vector_3<K> vec(const CGAL::Point_3<K>& p)
+{
+  typename K::Construct_vector_3 v = K().construct_vector_3_object();
+  return v(CGAL::ORIGIN, p);
+}
+template <typename K>
+CGAL::Vector_3<K> vec(const CGAL::Weighted_point_3<K>& wp)
+{
+  return vec(point(wp));
+}
+
+
+const int indices_table[4][3] = { { 3, 1, 2 },
+                                  { 3, 2, 0 },
+                                  { 3, 0, 1 },
+                                  { 2, 1, 0 } };
+
+int indices(const int& i, const int& j)
+{
+  CGAL_assertion(i < 4 && j < 3);
+  if(i < 4 && j < 3)
+    return indices_table[i][j];
+  else
+    return -1;
+}
+
+template<typename Gt, typename Point>
+typename Gt::FT dihedral_angle(const Point& p,
+                               const Point& q,
+                               const Point& r,
+                               const Point& s,
+                               const Gt& gt)
+{
+  return gt.compute_approximate_dihedral_angle_3_object()(p, q, r, s);
+}
+
+template<typename Point, typename Geom_traits>
+typename Geom_traits::FT min_dihedral_angle(const Point& p,
+                                            const Point& q,
+                                            const Point& r,
+                                            const Point& s,
+                                            const Geom_traits& gt)
+{
+  typedef typename Geom_traits::FT FT;
+  FT a = CGAL::abs(dihedral_angle(p, q, r, s, gt));
+  FT min_dh = a;
+
+  a = CGAL::abs(dihedral_angle(p, r, q, s, gt));
+  min_dh = (std::min)(a, min_dh);
+
+  a = CGAL::abs(dihedral_angle(p, s, q, r, gt));
+  min_dh = (std::min)(a, min_dh);
+
+  a = CGAL::abs(dihedral_angle(q, r, p, s, gt));
+  min_dh = (std::min)(a, min_dh);
+
+  a = CGAL::abs(dihedral_angle(q, s, p, r, gt));
+  min_dh = (std::min)(a, min_dh);
+
+  a = CGAL::abs(dihedral_angle(r, s, p, q, gt));
+  min_dh = (std::min)(a, min_dh);
+
+  return min_dh;
+}
+
+template<typename Tr>
+typename Tr::Geom_traits::FT min_dihedral_angle(const Tr& tr,
+                                                const typename Tr::Vertex_handle v0,
+                                                const typename Tr::Vertex_handle v1,
+                                                const typename Tr::Vertex_handle v2,
+                                                const typename Tr::Vertex_handle v3)
+{
+  return min_dihedral_angle(point(v0->point()),
+                            point(v1->point()),
+                            point(v2->point()),
+                            point(v3->point()),
+                            tr.geom_traits());
+}
+
+template<typename Tr>
+typename Tr::Geom_traits::FT min_dihedral_angle(const Tr& tr,
+                                                const typename Tr::Cell_handle c)
+{
+  return min_dihedral_angle(tr,
+                            c->vertex(0),
+                            c->vertex(1),
+                            c->vertex(2),
+                            c->vertex(3));
+}
+
+template<typename Tr>
+typename Tr::Geom_traits::Vector_3 facet_normal(const Tr& tr,
+                                                const typename Tr::Facet& f)
+{
+  const typename Tr::Geom_traits gt = tr.geom_traits();
+  typename Tr::Geom_traits::Construct_normal_3 cn
+    = gt.construct_normal_3_object();
+  return cn(point(f.first->vertex((f.second + 1) % 4)->point()),
+            point(f.first->vertex((f.second + 2) % 4)->point()),
+            point(f.first->vertex((f.second + 3) % 4)->point()));
+}
+
+template<typename Vh>
+std::pair<Vh, Vh> make_vertex_pair(const Vh v1, const Vh v2)
+{
+  if (v2 < v1) return std::make_pair(v2, v1);
+  else         return std::make_pair(v1, v2);
+}
+
+template<typename Tr>
+std::pair<typename Tr::Vertex_handle, typename Tr::Vertex_handle>
+make_vertex_pair(const typename Tr::Edge& e)
+{
+  typedef typename Tr::Vertex_handle Vertex_handle;
+  Vertex_handle v1 = e.first->vertex(e.second);
+  Vertex_handle v2 = e.first->vertex(e.third);
+  return make_vertex_pair(v1, v2);
+}
+
+template<typename Vh>
+CGAL::Triple<Vh, Vh, Vh> make_vertex_triple(const Vh vh0, const Vh vh1, const Vh vh2)
+{
+  CGAL::Triple<Vh, Vh, Vh> ft(vh0, vh1, vh2);
+  if (ft.template get<1>() < ft.template get<0>()) std::swap(ft.template get<0>(), ft.template get<1>());
+  if (ft.template get<2>() < ft.template get<1>()) std::swap(ft.template get<1>(), ft.template get<2>());
+  if (ft.template get<1>() < ft.template get<0>()) std::swap(ft.template get<0>(), ft.template get<1>());
+  return ft;
+}
+
+template<typename Vh>
+std::array<Vh, 3> make_vertex_array(const Vh vh0, const Vh vh1, const Vh vh2)
+{
+  std::array<Vh, 3> ft = { {vh0, vh1, vh2} };
+  if (ft[1] < ft[0]) std::swap(ft[0], ft[1]);
+  if (ft[2] < ft[1]) std::swap(ft[1], ft[2]);
+  if (ft[1] < ft[0]) std::swap(ft[0], ft[1]);
+  return ft;
+}
+
+template<typename Facet>
+Facet canonical_facet(const Facet& f)
+{
+  const typename Facet::first_type c = f.first;
+  const int i = f.second;
+  const typename Facet::first_type c2 = c->neighbor(i);
+  return (c2 < c) ? std::make_pair(c2, c2->index(c)) : std::make_pair(c, i);
+}
+
+template<typename VertexHandle>
+bool is_on_feature(const VertexHandle v)
+{
+  return (v->in_dimension() == 1 || v->in_dimension() == 0);
+}
+
+template<typename Tr>
+bool is_well_oriented(const Tr& tr,
+                      const typename Tr::Vertex_handle v0,
+                      const typename Tr::Vertex_handle v1,
+                      const typename Tr::Vertex_handle v2,
+                      const typename Tr::Vertex_handle v3)
+{
+  return CGAL::POSITIVE == tr.geom_traits().orientation_3_object()(
+           point(v0->point()),
+           point(v1->point()),
+           point(v2->point()),
+           point(v3->point()));
+}
+
+template<typename Tr>
+bool is_well_oriented(const Tr& tr, const typename Tr::Cell_handle ch)
+{
+  return is_well_oriented(tr, ch->vertex(0), ch->vertex(1),
+                          ch->vertex(2), ch->vertex(3));
+}
+
+template<typename C3T3, typename CellSelector>
+bool is_boundary(const C3T3& c3t3,
+                 const typename C3T3::Facet& f,
+                 const CellSelector& cell_selector)
+{
+  return c3t3.is_in_complex(f)
+         || cell_selector(f.first) != cell_selector(f.first->neighbor(f.second));
+}
+
+template<typename C3T3, typename CellSelector>
+bool is_boundary(const C3T3& c3t3,
+                 const typename C3T3::Triangulation::Edge& e,
+                 CellSelector cell_selector)
+{
+  typedef typename C3T3::Triangulation   Tr;
+  typedef typename Tr::Facet_circulator  Facet_circulator;
+  typedef typename Tr::Facet             Facet;
+
+  Facet_circulator fcirc = c3t3.triangulation().incident_facets(e);
+  Facet_circulator fend = fcirc;
+
+  do
+  {
+    const Facet& f = *fcirc;
+    if (is_boundary(c3t3, f, cell_selector))
+      return true;
+  }
+  while (++fcirc != fend);
+
+  return false;
+}
+
+template<typename C3t3, typename CellSelector>
+bool is_boundary_edge(const typename C3t3::Vertex_handle& v0,
+                      const typename C3t3::Vertex_handle& v1,
+                      const C3t3& c3t3,
+                      const CellSelector& cell_selector)
+{
+  typedef typename C3t3::Edge        Edge;
+  typedef typename C3t3::Cell_handle Cell_handle;
+
+  Cell_handle cell;
+  int i0, i1;
+  if (c3t3.triangulation().tds().is_edge(v0, v1, cell, i0, i1))
+    return is_boundary(c3t3, Edge(cell, i0, i1), cell_selector);
+  else
+    return false;
+}
+
+template<typename C3t3, typename CellSelector>
+bool is_boundary_vertex(const typename C3t3::Vertex_handle& v,
+                        const C3t3& c3t3,
+                        CellSelector cell_selector)
+{
+  typedef typename C3t3::Facet Facet;
+  std::vector<Facet> facets;
+  c3t3.triangulation().incident_facets(v, std::back_inserter(facets));
+
+  for(const Facet& f : facets)
+  {
+    if (c3t3.is_in_complex(f))
+      return true;
+    if (cell_selector(f.first) ^ cell_selector(f.first->neighbor(f.second)))
+      return true;
+  }
+  return false;
+}
+
+template<typename C3t3>
+typename C3t3::Surface_patch_index surface_patch_index(const typename C3t3::Vertex_handle v,
+    const C3t3& c3t3)
+{
+  typedef typename C3t3::Surface_patch_index Surface_patch_index;
+  typedef typename C3t3::Facet Facet;
+  std::vector<Facet> facets;
+  c3t3.triangulation().incident_facets(v, std::back_inserter(facets));
+
+  for(const Facet& f : facets)
+  {
+    if (c3t3.is_in_complex(f))
+      return c3t3.surface_patch_index(f);
+  }
+  return Surface_patch_index();
+}
+
+template<typename C3t3>
+bool is_edge_in_complex(const typename C3t3::Vertex_handle& v0,
+                        const typename C3t3::Vertex_handle& v1,
+                        const C3t3& c3t3)
+{
+  typedef typename C3t3::Edge        Edge;
+  typedef typename C3t3::Cell_handle Cell_handle;
+
+  Cell_handle cell;
+  int i0, i1;
+  if (c3t3.triangulation().tds().is_edge(v0, v1, cell, i0, i1))
+    return c3t3.is_in_complex(Edge(cell, i0, i1));
+  else
+    return false;
+}
+
+template<typename C3t3, typename OutputIterator>
+OutputIterator incident_subdomains(const typename C3t3::Vertex_handle v,
+                                   const C3t3& c3t3,
+                                   OutputIterator oit)
+{
+  typedef typename C3t3::Triangulation::Cell_handle Cell_handle;
+  std::vector<Cell_handle> cells;
+  c3t3.triangulation().incident_cells(v, std::back_inserter(cells));
+
+  for (std::size_t i = 0; i < cells.size(); ++i)
+    *oit++ = cells[i]->subdomain_index();
+
+  return oit;
+}
+
+template<typename C3t3, typename OutputIterator>
+OutputIterator incident_subdomains(const typename C3t3::Edge& e,
+                                   const C3t3& c3t3,
+                                   OutputIterator oit)
+{
+  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+
+  Cell_circulator circ = c3t3.triangulation().incident_cells(e);
+  Cell_circulator end = circ;
+  do
+  {
+    *oit++ = circ->subdomain_index();
+  } while (++circ != end);
+
+  return oit;
+}
+
+template<typename C3t3, typename OutputIterator>
+OutputIterator incident_surface_patches(const typename C3t3::Edge& e,
+                                        const C3t3& c3t3,
+                                        OutputIterator oit)
+{
+  typedef typename C3t3::Triangulation::Facet_circulator Facet_circulator;
+  typedef typename C3t3::Triangulation::Facet Facet;
+
+  Facet_circulator circ = c3t3.triangulation().incident_facets(e);
+  Facet_circulator end = circ;
+  do
+  {
+    const Facet& f = *circ;
+    if(c3t3.is_in_complex(f))
+      *oit++ = c3t3.surface_patch_index(f);
+  }
+  while (++circ != end);
+
+  return oit;
+}
+
+template<typename C3t3>
+std::size_t nb_incident_subdomains(const typename C3t3::Vertex_handle v,
+                                   const C3t3& c3t3)
+{
+  typedef typename C3t3::Subdomain_index Subdomain_index;
+
+  boost::unordered_set<Subdomain_index> indices;
+  incident_subdomains(v, c3t3, std::inserter(indices, indices.begin()));
+
+  return indices.size();
+}
+
+template<typename C3t3>
+std::size_t nb_incident_subdomains(const typename C3t3::Edge& e,
+                                   const C3t3& c3t3)
+{
+  typedef typename C3t3::Subdomain_index Subdomain_index;
+
+  boost::unordered_set<Subdomain_index> indices;
+  incident_subdomains(e, c3t3, std::inserter(indices, indices.begin()));
+
+  return indices.size();
+}
+
+template <typename C3t3>
+std::size_t nb_incident_surface_patches(const typename C3t3::Edge& e,
+                                        const C3t3& c3t3)
+{
+  typedef typename C3t3::Surface_patch_index Surface_patch_index;
+
+  boost::unordered_set<Surface_patch_index> indices;
+  incident_surface_patches(e, c3t3, std::inserter(indices, indices.begin()));
+
+  return indices.size();
+}
+
+template<typename C3t3>
+std::size_t nb_incident_complex_edges(const typename C3t3::Vertex_handle v,
+                                      const C3t3& c3t3)
+{
+  typedef typename C3t3::Edge Edge;
+  boost::unordered_set<Edge> edges;
+  c3t3.triangulation().finite_incident_edges(v, std::inserter(edges, edges.begin()));
+
+  std::size_t count = 0;
+  for (const Edge& e : edges)
+  {
+    if (c3t3.is_in_complex(e))
+      ++count;
+  }
+  return count;
+}
+
+
+template<typename C3t3>
+bool is_feature(const typename C3t3::Vertex_handle v,
+                const typename C3t3::Vertex_handle neighbor,
+                const C3t3& c3t3)
+{
+  typename C3t3::Cell_handle ch;
+  int i0, i1;
+  if (c3t3.triangulation().is_edge(v, neighbor, ch, i0, i1))
+  {
+    typename C3t3::Edge edge(ch, i0, i1);
+    return c3t3.is_in_complex(edge);
+  }
+  return false;
+}
+
+template<typename C3t3>
+bool is_feature(const typename C3t3::Vertex_handle v, const C3t3& c3t3)
+{
+  typedef typename C3t3::Edge Edge;
+
+  if (c3t3.number_of_corners() > 0)
+  {
+    return c3t3.is_in_complex(v);
+  }
+  else if (nb_incident_subdomains(v, c3t3) > 3)
+  {
+    std::vector<Edge> edges;
+    c3t3.triangulation().finite_incident_edges(v, std::back_inserter(edges));
+
+    int feature_count = 0;
+    for(const Edge& ei : edges)
+    {
+      if (c3t3.is_in_complex(ei))
+      {
+        feature_count++;
+        if (feature_count >= 3)
+          return true;
+      }
+    }
+  }
+  return false;
+}
+
+/**
+* returns true iff `v` is on the outer hull of c3t3.triangulation()
+* i.e. finite and incident to at least one infinite cell
+*/
+template<typename C3t3>
+bool is_on_convex_hull(const typename C3t3::Vertex_handle v,
+                       const C3t3& c3t3)
+{
+  if (v == c3t3.triangulation().infinite_vertex())
+    return true;
+
+  //on hull == incident to infinite cell
+  typedef typename C3t3::Triangulation::Cell_handle Cell_handle;
+
+  std::vector<Cell_handle> cells;
+  c3t3.triangulation().incident_cells(v, std::back_inserter(cells));
+  for (Cell_handle ci : cells)
+  {
+    if (c3t3.triangulation().is_infinite(ci))
+      return true;
+  }
+  return false;
+}
+
+/**
+* returns true iff `edge` is on the outer hull
+* of c3t3.triangulation()
+* i.e. finite and incident to at least one infinite cell
+*/
+template<typename C3t3>
+bool is_on_convex_hull(const typename C3t3::Edge & edge,
+                       const C3t3& c3t3)
+{
+  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+  Cell_circulator circ = c3t3.triangulation().incident_cells(edge);
+  Cell_circulator done = circ;
+  do
+  {
+    if (c3t3.triangulation().is_infinite(circ))
+      return true;
+  } while (++circ != done);
+
+  return false;
+}
+
+template<typename C3t3, typename CellSelector>
+bool is_outside(const typename C3t3::Edge & edge,
+                const C3t3& c3t3,
+                CellSelector cell_selector)
+{
+  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+  Cell_circulator circ = c3t3.triangulation().incident_cells(edge);
+  Cell_circulator done = circ;
+  do
+  {
+    // is cell in complex?
+    if (c3t3.is_in_complex(circ))
+      return false;
+    // does circ belong to the selection?
+    if (cell_selector(circ))
+      return false;
+
+    ++circ;
+  } while (circ != done);
+
+  return true; //all incident cells are outside or infinite
+}
+
+template<typename C3t3, typename CellSelector>
+bool is_selected(const typename C3t3::Vertex_handle v,
+                 const C3t3& c3t3,
+                 CellSelector cell_selector)
+{
+  typedef typename C3t3::Triangulation::Cell_handle Cell_handle;
+
+  std::vector<Cell_handle> cells;
+  c3t3.triangulation().incident_cells(v, std::back_inserter(cells));
+
+  for(Cell_handle c : cells)
+  {
+    if (cell_selector(c))
+      return true;
+  }
+  return false;
+}
+
+template<typename C3t3, typename CellSelector>
+bool is_internal(const typename C3t3::Edge& edge,
+                 const C3t3& c3t3,
+                 CellSelector cell_selector)
+{
+  const typename C3t3::Vertex_handle vs = edge.first->vertex(edge.second);
+  const typename C3t3::Vertex_handle vt = edge.first->vertex(edge.third);
+
+  typedef typename C3t3::Triangulation::Cell_circulator Cell_circulator;
+  Cell_circulator circ = c3t3.triangulation().incident_cells(edge);
+  Cell_circulator done = circ;
+
+  const typename C3t3::Subdomain_index si = circ->subdomain_index();
+  do
+  {
+    if (c3t3.triangulation().is_infinite(circ))
+      return false;
+    if (si != circ->subdomain_index())
+      return false;
+    if (!cell_selector(circ))
+      return false;
+    if (c3t3.is_in_complex(
+          circ,
+          CGAL::Triangulation_utils_3::next_around_edge(circ->index(vs), circ->index(vt))))
+      return false;
+  } while (++circ != done);
+
+  return true;
+}
+
+template<typename Gt>
+void normalize(typename Gt::Vector_3& v, const Gt& gt)
+{
+  typedef typename Gt::FT       FT;
+
+  const FT norm = CGAL::approximate_sqrt(gt.compute_squared_length_3_object()(v));
+  if (norm != FT(0))
+    v = gt.construct_divided_vector_3_object()(v, norm);
+}
+
+template<typename Facet, typename Gt>
+typename Gt::Vector_3 normal(const Facet& f, const Gt& gt)
+{
+  typedef typename Gt::Vector_3 Vector_3;
+  typedef typename Gt::Point_3  Point;
+  typedef typename Gt::FT       FT;
+
+  Point p0 = point(f.first->vertex((f.second + 1) % 4)->point());
+  Point p1 = point(f.first->vertex((f.second + 2) % 4)->point());
+  const Point& p2 = point(f.first->vertex((f.second + 3) % 4)->point());
+
+  if (f.second % 2 == 0)//equivalent to the commented orientation test
+    std::swap(p0, p1);
+
+  Vector_3 n = gt.construct_cross_product_vector_3_object()(
+                 gt.construct_vector_3_object()(p1, p2),
+                 gt.construct_vector_3_object()(p1, p0));
+
+  //cross-product(AB, AC)'s norm is the area of the parallelogram
+  //formed by these 2 vectors.
+  //the triangle's area is half of it
+  return gt.construct_scaled_vector_3_object()(n, FT(1) / FT(2));
+}
+
+template<typename C3t3, typename CellSelector, typename OutputIterator>
+OutputIterator get_internal_edges(const C3t3& c3t3,
+                                  CellSelector cell_selector,
+                                  OutputIterator oit)/*holds Edges*/
+{
+  for (typename C3t3::Triangulation::Finite_edges_iterator
+       eit = c3t3.triangulation().finite_edges_begin();
+       eit != c3t3.triangulation().finite_edges_end();
+       ++eit)
+  {
+    const typename C3t3::Edge& e = *eit;
+    if (is_internal(e, c3t3, cell_selector))
+    {
+      *oit++ = make_vertex_pair<typename C3t3::Triangulation>(e);
+    }
+  }
+  return oit;
+}
+
+template<typename C3t3, typename CellSelector>
+bool topology_test(const typename C3t3::Edge& edge,
+                   const C3t3& c3t3,
+                   const CellSelector& cell_selector)
+{
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+  typedef typename C3t3::Cell_handle   Cell_handle;
+  typedef typename C3t3::Edge          Edge;
+  typedef typename C3t3::Facet         Facet;
+  typedef typename C3t3::Triangulation::Facet_circulator Facet_circulator;
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+
+  // the "topology test" checks that :
+  // no incident non-boundary facet has 3 boundary edges
+  // no incident boundary facet has 3 feature edges
+
+  Facet_circulator fcirc = c3t3.triangulation().incident_facets(edge);
+  Facet_circulator fdone = fcirc;
+  do
+  {
+    if (c3t3.triangulation().is_infinite(fcirc->first))
+      continue;
+
+    const Facet& f = *fcirc;
+    if (is_boundary(c3t3, f, cell_selector))
+      //boundary : check that facet does not have 3 feature edges
+    {
+      //Get the ids of the opposite vertices
+      for (int i = 1; i < 4; i++)
+      {
+        Vertex_handle vi = f.first->vertex((f.second + i) % 4);
+        if (vi != v0 && vi != v1 && nb_incident_subdomains(vi, c3t3) > 1)
+        {
+          if (is_edge_in_complex(v0, vi, c3t3)
+              && is_edge_in_complex(v1, vi, c3t3))
+            return false;
+        }
+      }
+    }
+    else //non-boundary : check that facet does not have 3 boundary edges
+    {
+      const Cell_handle circ = f.first;
+      const int i = f.second;
+      if (is_boundary(c3t3, Edge(circ, (i + 1) % 4, (i + 2) % 4), cell_selector)
+          && is_boundary(c3t3, Edge(circ, (i + 2) % 4, (i + 3) % 4), cell_selector)
+          && is_boundary(c3t3, Edge(circ, (i + 3) % 4, (i + 1) % 4), cell_selector))
+        return false;
+    }
+  } while (++fcirc != fdone);
+
+  return true;
+}
+
+template<typename C3t3>
+Subdomain_relation compare_subdomains(const typename C3t3::Vertex_handle v0,
+                                      const typename C3t3::Vertex_handle v1,
+                                      const C3t3& c3t3)
+{
+  typedef typename C3t3::Subdomain_index Subdomain_index;
+
+  std::vector<Subdomain_index> subdomains_v0;
+  incident_subdomains(v0, c3t3, std::back_inserter(subdomains_v0));
+  std::sort(subdomains_v0.begin(), subdomains_v0.end());
+
+  std::vector<Subdomain_index> subdomains_v1;
+  incident_subdomains(v1, c3t3, std::back_inserter(subdomains_v1));
+  std::sort(subdomains_v1.begin(), subdomains_v1.end());
+
+  if (subdomains_v0.size() == subdomains_v1.size())
+  {
+    for (unsigned int i = 0; i < subdomains_v0.size(); i++)
+      if (subdomains_v0[i] != subdomains_v1[i])
+        return DIFFERENT;
+    return EQUAL;
+  }
+  else
+  {
+    std::vector<Subdomain_index>
+    intersection((std::min)(subdomains_v0.size(), subdomains_v1.size()), -1);
+    typename std::vector<Subdomain_index>::iterator
+    end_it = std::set_intersection(subdomains_v0.begin(), subdomains_v0.end(),
+                                   subdomains_v1.begin(), subdomains_v1.end(),
+                                   intersection.begin());
+    std::ptrdiff_t intersection_size = (end_it - intersection.begin());
+
+    if (subdomains_v0.size() > subdomains_v1.size()
+        && intersection_size == std::ptrdiff_t(subdomains_v1.size()))
+    {
+      return INCLUDES;
+    }
+    else if (intersection_size == std::ptrdiff_t(subdomains_v0.size())) {
+      return INCLUDED;
+    }
+  }
+  return DIFFERENT;
+}
+
+template<typename C3t3, typename CellSelector>
+void get_edge_info(const typename C3t3::Edge& edge,
+                   bool& update_v0,
+                   bool& update_v1,
+                   const C3t3& c3t3,
+                   const CellSelector& cell_selector)
+{
+  typedef typename C3t3::Vertex_handle Vertex_handle;
+
+  update_v0 = false;
+  update_v1 = false;
+
+  const Vertex_handle v0 = edge.first->vertex(edge.second);
+  const Vertex_handle v1 = edge.first->vertex(edge.third);
+
+  const int dim0 = c3t3.in_dimension(v0);
+  const int dim1 = c3t3.in_dimension(v1);
+
+  if (dim0 == 3)
+  {
+    CGAL_assertion(!is_on_convex_hull(v0, c3t3));
+    update_v0 = true;
+    if (dim1 == 3)
+    {
+      CGAL_assertion(!is_on_convex_hull(v1, c3t3));
+      update_v1 = true;
+      return;
+    }
+    else // dim1 is 2, 1, or 0
+      return;
+  }
+  else if (dim1 == 3)
+  {
+    update_v1 = true;
+    return;
+  }
+
+  // from now on, all cases lie on surfaces, or between surfaces
+  CGAL_assertion(dim0 != 3 && dim1 != 3);
+
+  //feature edges and feature vertices
+  if (dim0 < 2 || dim1 < 2)
+  {
+    if (c3t3.is_in_complex(edge))
+    {
+      if (!topology_test(edge, c3t3, cell_selector))
+      {
+#ifdef CGAL_DEBUG_TET_REMESHING_IN_PLUGIN
+        nb_topology_test++;
+#endif
+        return;
+      }
+      const std::size_t nb_si_v0 = nb_incident_subdomains(v0, c3t3);
+      const std::size_t nb_si_v1 = nb_incident_subdomains(v1, c3t3);
+
+      if (nb_si_v0 > nb_si_v1) {
+        if (!c3t3.is_in_complex(v1))
+          update_v1 = true;
+      }
+      else if (nb_si_v1 > nb_si_v0) {
+        if (!c3t3.is_in_complex(v0))
+          update_v0 = true;
+      }
+      else {
+        if (!c3t3.is_in_complex(v0))
+          update_v0 = true;
+        if (!c3t3.is_in_complex(v1))
+          update_v1 = true;
+      }
+    }
+    return;
+  }
+
+  if (dim0 == 2 && dim1 == 2)
+  {
+    if (is_boundary(c3t3, edge, cell_selector))
+    {
+      if (!topology_test(edge, c3t3, cell_selector))
+        return;
+      Subdomain_relation subdomain_rel = compare_subdomains(v0, v1, c3t3);
+
+      //Vertices on the same surface
+      if (subdomain_rel == INCLUDES) {
+        update_v1 = true;
+      }
+      else if (subdomain_rel == INCLUDED) {
+        update_v0 = true;
+      }
+      else if (subdomain_rel == EQUAL)
+      {
+        if (c3t3.number_of_edges() == 0)
+        {
+          update_v0 = true;
+          update_v1 = true;
+        }
+        else
+        {
+          const bool v0_on_feature = is_on_feature(v0);
+          const bool v1_on_feature = is_on_feature(v1);
+
+          if (v0_on_feature && v1_on_feature) {
+            if (c3t3.is_in_complex(edge)) {
+              if (!c3t3.is_in_complex(v0))
+                update_v0 = true;
+              if (!c3t3.is_in_complex(v1))
+                update_v1 = true;
+            }
+          }
+          else {
+            if (!v0_on_feature) {
+              update_v0 = true;
+            }
+            if (!v1_on_feature) {
+              update_v1 = true;
+            }
+          }
+        }
+      }
+    }
+  }
+}
+
+namespace debug
+{
+
+// forward-declaration
+template<typename Tr, typename CellRange>
+void dump_cells(const CellRange& cells, const char* filename);
+
+template <typename Bimap>
+void dump_edges(const Bimap& edges, const char* filename)
+{
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+
+  BOOST_FOREACH(typename Bimap::left_const_reference it, edges.left)
+  {
+    ofs << "2 " << point(it.first.first->point())
+        << " " << point(it.first.second->point()) << std::endl;
+  }
+  ofs.close();
+}
+
+template<typename Facet, typename OutputStream>
+void dump_facet(const Facet& f, OutputStream& os)
+{
+  os << "4 ";
+  os << point(f.first->vertex((f.second + 1) % 4)->point()) << " "
+     << point(f.first->vertex((f.second + 2) % 4)->point()) << " "
+     << point(f.first->vertex((f.second + 3) % 4)->point()) << " "
+     << point(f.first->vertex((f.second + 1) % 4)->point());
+  os << std::endl;
+}
+
+template<typename FacetRange>
+void dump_facets(const FacetRange& facets, const char* filename)
+{
+  std::ofstream os(filename);
+  for (typename FacetRange::value_type f : facets)
+  {
+    dump_facet(f, os);
+  }
+  os.close();
+}
+
+template<typename CellRange>
+void dump_polylines(const CellRange& cells, const char* filename)
+{
+  std::ofstream ofs(filename);
+  if (!ofs) return;
+
+  for (typename CellRange::const_iterator it = cells.begin();
+       it != cells.end(); ++it)
+  {
+    for (int i = 0; i < 4; ++i)
+      dump_facet(std::make_pair(*it, i), ofs);
+  }
+  ofs.close();
+}
+
+template<typename Tr>
+bool are_cell_orientations_valid(const Tr& tr)
+{
+  typedef typename Tr::Geom_traits::Point_3 Point_3;
+  typedef typename Tr::Facet                Facet;
+
+  std::set<Facet> facets;
+  for (const typename Tr::Cell_handle ch : tr.finite_cell_handles())
+  {
+    const Point_3& p0 = point(ch->vertex(0)->point());
+    const Point_3& p1 = point(ch->vertex(1)->point());
+    const Point_3& p2 = point(ch->vertex(2)->point());
+    const Point_3& p3 = point(ch->vertex(3)->point());
+
+    const CGAL::Orientation o = CGAL::orientation(p0, p1, p2, p3);
+    if (o != CGAL::POSITIVE)
+    {
+      facets.insert(canonical_facet(Facet(ch, 0)));
+      facets.insert(canonical_facet(Facet(ch, 1)));
+      facets.insert(canonical_facet(Facet(ch, 2)));
+      facets.insert(canonical_facet(Facet(ch, 3)));
+    }
+  }
+  if (!facets.empty())
+  {
+    std::cerr << "Warning : there are inverted cells!\n"
+              << "\tSee cells_with_negative_volume.polylines.txt" << std::endl;
+    dump_facets(facets, "cells_with_negative_volume.polylines.txt");
+  }
+  return facets.empty();
+}
+
+template<typename Tr>
+void dump_surface_off(const Tr& tr, const char* filename)
+{
+  typedef typename Tr::Vertex_handle              Vertex_handle;
+  typedef typename Tr::Cell_handle                Cell_handle;
+  typedef typename Tr::Finite_facets_iterator     Finite_facets_iterator;
+  typedef boost::bimap<Vertex_handle, int>                   Bimap_t;
+  typedef typename Bimap_t::left_map::value_type             value_type;
+
+  //collect vertices
+  Bimap_t vertices;
+  std::size_t nbf = 0;
+  int index = 0;
+  for (Finite_facets_iterator fit = tr.finite_facets_begin();
+       fit != tr.finite_facets_end(); ++fit)
+  {
+    Cell_handle c = fit->first;
+    int i = fit->second;
+    if (tr.is_infinite(c) || tr.is_infinite(c->neighbor(i)))
+    {
+      nbf++;
+      for (int j = 1; j < 4; ++j)
+      {
+        Vertex_handle vij = c->vertex((i + j) % 4);
+        if (vertices.left.find(vij) == vertices.left.end())
+          vertices.left.insert(value_type(vij, index++));
+      }
+    }
+  }
+
+  //write header
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  ofs << "OFF" << std::endl;
+  ofs << vertices.left.size() << " " << nbf << " 0" << std::endl << std::endl;
+
+  // write vertices
+  for (typename Bimap_t::right_iterator vit = vertices.right.begin();
+       vit != vertices.right.end(); ++vit)
+  {
+    ofs << point(vit->second->point()) << std::endl;
+  }
+
+  //write facets
+  std::size_t nbf_print = 0;
+  for (Finite_facets_iterator fit = tr.finite_facets_begin();
+       fit != tr.finite_facets_end(); ++fit)
+  {
+    Cell_handle c = fit->first;
+    int i = fit->second;
+    if (tr.is_infinite(c) || tr.is_infinite(c->neighbor(i)))
+    {
+      ofs << "3  " << vertices.left.at(c->vertex((i + 1) % 4)) << " "
+          << vertices.left.at(c->vertex((i + 2) % 4)) << " "
+          << vertices.left.at(c->vertex((i + 3) % 4)) << std::endl;
+      ++nbf_print;
+    }
+  }
+  CGAL_assertion(nbf == nbf_print);
+
+  ofs.close();
+}
+
+template<typename CellRange, typename Tr>
+void dump_cells_off(const CellRange& cells, const Tr& /*tr*/, const char* filename)
+{
+  typedef typename Tr::Vertex_handle              Vertex_handle;
+  typedef typename Tr::Cell_handle                Cell_handle;
+  typedef boost::bimap<Vertex_handle, int>        Bimap_t;
+  typedef typename Bimap_t::left_map::value_type  value_type;
+
+  Bimap_t vertices;
+  int index = 0;
+  boost::unordered_set<std::array<Vertex_handle, 3> > facets;
+
+  for (Cell_handle c : cells)
+  {
+    //collect vertices
+    for (int i = 0; i < 4; ++i)
+    {
+      Vertex_handle vi = c->vertex(i);
+      if (vertices.left.find(c->vertex(i)) == vertices.left.end())
+        vertices.left.insert(value_type(vi, index++));
+    }
+    //collect facets
+    for (int i = 0; i < 4; ++i)
+    {
+      //if (tr.is_infinite(c->neighbor(i)))
+      {
+        std::array<Vertex_handle, 3> fi = make_vertex_array(c->vertex((i + 1) % 4),
+          c->vertex((i + 2) % 4),
+          c->vertex((i + 3) % 4));
+          facets.insert(fi);
+      }
+    }
+  }
+
+  //write header
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  ofs << "OFF" << std::endl;
+  ofs << vertices.size() << " " << facets.size() << " 0" << std::endl << std::endl;
+
+  for(const typename Bimap_t::right_map::value_type& v : vertices.right)
+    ofs << v.second->point().x() << " "
+        << v.second->point().y() << " "
+        << v.second->point().z() << std::endl;
+
+  for(const std::array<Vertex_handle, 3>& f : facets)
+    ofs << "3  " << vertices.left.at(f[0]) << " "
+                 << vertices.left.at(f[1]) << " "
+                 << vertices.left.at(f[2]) << std::endl;
+
+  ofs.close();
+}
+
+template<typename Tr>
+void dump_cells_off(const Tr& tr, const char* filename)
+{
+  typedef typename Tr::Vertex_handle              Vertex_handle;
+  typedef typename Tr::Cell_handle                Cell_handle;
+  typedef typename Tr::Finite_facets_iterator     Finite_facets_iterator;
+  typedef typename Tr::Finite_vertices_iterator   Finite_vertices_iterator;
+  typedef boost::bimap<Vertex_handle, int>                   Bimap_t;
+  typedef typename Bimap_t::left_map::value_type             value_type;
+
+  //write header
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  ofs << "OFF" << std::endl;
+  ofs << tr.number_of_vertices()
+      << " " << tr.number_of_finite_facets() << " 0" << std::endl << std::endl;
+
+  //collect and write vertices
+  Bimap_t vertices;
+  int index = 0;
+  for (Finite_vertices_iterator vit = tr.finite_vertices_begin();
+       vit != tr.finite_vertices_end(); ++vit)
+  {
+    vertices.left.insert(value_type(vit, index++));
+    ofs << vit->point().x() << " "
+        << vit->point().y() << " "
+        << vit->point().z() << std::endl;
+  }
+
+  //write facets
+  for (Finite_facets_iterator fit = tr.finite_facets_begin();
+       fit != tr.finite_facets_end(); ++fit)
+  {
+    Cell_handle c = fit->first;
+    int i = fit->second;
+    ofs << "3  " << vertices.left.at(c->vertex((i + 1) % 4)) << " "
+        << vertices.left.at(c->vertex((i + 2) % 4)) << " "
+        << vertices.left.at(c->vertex((i + 3) % 4)) << std::endl;
+  }
+  ofs.close();
+}
+
+template<typename CellRange>
+void dump_cells_polylines(const CellRange& cells, const char* filename)
+{
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  for (auto c : cells)
+  {
+    ofs << "2 " << point(c->vertex(0)->point()) << " "
+                << point(c->vertex(1)->point()) <<std::endl;
+    ofs << "2 " << point(c->vertex(0)->point()) << " "
+                << point(c->vertex(2)->point()) << std::endl;
+    ofs << "2 " << point(c->vertex(0)->point()) << " "
+                << point(c->vertex(3)->point()) << std::endl;
+    ofs << "2 " << point(c->vertex(1)->point()) << " "
+                << point(c->vertex(2)->point()) << std::endl;
+    ofs << "2 " << point(c->vertex(1)->point()) << " "
+                << point(c->vertex(3)->point()) << std::endl;
+    ofs << "2 " << point(c->vertex(2)->point()) << " "
+                << point(c->vertex(3)->point()) << std::endl;
+  }
+  ofs.close();
+}
+
+template<typename Tr, typename CellRange, typename IndexRange>
+void dump_cells(const CellRange& cells,
+                const IndexRange& indices,
+                const char* filename)
+{
+  typedef typename Tr::Vertex_handle                         Vertex_handle;
+  typedef typename Tr::Point                                 Point;
+  typedef boost::bimap<Vertex_handle, int>                   Bimap_t;
+  typedef typename Bimap_t::left_map::value_type             value_type;
+
+  CGAL_assertion(indices.empty() || cells.size() == indices.size());
+
+  //collect vertices
+  Bimap_t vertices;
+  int index = 1;
+  for (typename CellRange::const_iterator cit = cells.begin();
+       cit != cells.end();
+       ++cit)
+  {
+    for (int i = 0; i < 4; ++i)
+    {
+      Vertex_handle vi = (*cit)->vertex(i);
+      if (vertices.left.find(vi) == vertices.left.end())
+        vertices.left.insert(value_type(vi, index++));
+    }
+  }
+
+  //write cells
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  ofs << "MeshVersionFormatted 1" << std::endl;
+  ofs << "Dimension 3" << std::endl;
+  ofs << "Vertices" << std::endl << vertices.size() << std::endl;
+  for (typename Bimap_t::right_const_iterator vit = vertices.right.begin();
+       vit != vertices.right.end();
+       ++vit)
+  {
+    const Point& p = vit->second->point();
+    ofs << p.x() << " " << p.y() << " " << p.z() << " 2" << std::endl;
+  }
+  ofs << "Tetrahedra " << std::endl << cells.size() << std::endl;
+  typename IndexRange::const_iterator iit = indices.begin();
+  for (typename CellRange::const_iterator cit = cells.begin();
+       cit != cells.end();
+       ++cit)
+  {
+    ofs << vertices.left.at((*cit)->vertex(0))
+        << " " << vertices.left.at((*cit)->vertex(1))
+        << " " << vertices.left.at((*cit)->vertex(2))
+        << " " << vertices.left.at((*cit)->vertex(3));
+
+    if (iit == indices.end())
+      ofs << " 1" << std::endl;
+    else
+    {
+      ofs << " " << (*iit) << std::endl;
+      ++iit;
+    }
+  }
+  ofs << "End" << std::endl;
+  ofs.close();
+}
+
+template<typename Tr, typename CellRange>
+void dump_cells(const CellRange& cells, const char* filename)
+{
+  std::vector<int> indices;
+  dump_cells<Tr>(cells, indices, filename);
+}
+
+template<typename Tr>
+void dump_cells_in_complex(const Tr& tr, const char* filename)
+{
+  std::vector<typename Tr::Cell_handle> cells;
+  std::vector<typename Tr::Cell::Subdomain_index> indices;
+
+  for (typename Tr::Finite_cells_iterator cit = tr.finite_cells_begin();
+       cit != tr.finite_cells_end(); ++cit)
+  {
+    if (cit->subdomain_index() > 0)
+    {
+      cells.push_back(cit);
+      indices.push_back(cit->subdomain_index());
+    }
+  }
+  dump_cells<Tr>(cells, indices, filename);
+}
+
+template<typename C3t3>
+void dump_facets_in_complex(const C3t3& c3t3, const char* filename)
+{
+  typedef typename C3t3::Triangulation              Tr;
+  typedef typename Tr::Vertex_handle                Vertex_handle;
+  typedef typename Tr::Cell_handle                  Cell_handle;
+  typedef typename C3t3::Facets_in_complex_iterator Facets_in_complex_iterator;
+  typedef boost::bimap<Vertex_handle, int>          Bimap_t;
+  typedef typename Bimap_t::left_map::value_type  value_type;
+
+  //collect vertices
+  Bimap_t vertices;
+  std::size_t nbf = 0;
+  int index = 0;
+  for (Facets_in_complex_iterator fit = c3t3.facets_in_complex_begin();
+       fit != c3t3.facets_in_complex_end(); ++fit)
+  {
+    Cell_handle c = fit->first;
+    int i = fit->second;
+
+    nbf++;
+    for (int j = 1; j < 4; ++j)
+    {
+      Vertex_handle vij = c->vertex((i + j) % 4);
+      if (vertices.left.find(vij) == vertices.left.end())
+        vertices.left.insert(value_type(vij, index++));
+    }
+  }
+
+  //write header
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  ofs << "OFF" << std::endl;
+  ofs << vertices.left.size() << " " << nbf << " 0" << std::endl << std::endl;
+
+  // write vertices
+  for (typename Bimap_t::right_iterator vit = vertices.right.begin();
+       vit != vertices.right.end(); ++vit)
+  {
+    ofs << point(vit->second->point()) << std::endl;
+  }
+
+  //write facets
+  std::size_t nbf_print = 0;
+  for (Facets_in_complex_iterator fit = c3t3.facets_in_complex_begin();
+       fit != c3t3.facets_in_complex_end(); ++fit)
+  {
+    Cell_handle c = fit->first;
+    int i = fit->second;
+    ofs << "3  " << vertices.left.at(c->vertex((i + 1) % 4)) << " "
+        << vertices.left.at(c->vertex((i + 2) % 4)) << " "
+        << vertices.left.at(c->vertex((i + 3) % 4)) << std::endl;
+    ++nbf_print;
+  }
+  CGAL_assertion(nbf == nbf_print);
+
+  ofs.close();
+}
+
+template<typename C3T3>
+void dump_edges_in_complex(const C3T3& c3t3, const char* filename)
+{
+  std::ofstream ofs(filename);
+  ofs.precision(17);
+  for (typename C3T3::Edges_in_complex_iterator eit = c3t3.edges_in_complex_begin();
+       eit != c3t3.edges_in_complex_end(); ++eit)
+  {
+    const typename C3T3::Edge& e = *eit;
+    ofs << "2 "
+        << point(e.first->vertex(e.second)->point()) << " "
+        << point(e.first->vertex(e.third)->point()) << "\n";
+  }
+  ofs.close();
+}
+
+template<typename Tr, typename CellSelector>
+void dump_cells_with_small_dihedral_angle(const Tr& tr,
+    const double angle_bound,
+    CellSelector cell_select,
+    const char* filename)
+{
+  typedef typename Tr::Cell_handle           Cell_handle;
+  typedef typename Tr::Cell::Subdomain_index Subdomain_index;
+  std::vector<Cell_handle>     cells;
+  std::vector<Subdomain_index> indices;
+
+  for (typename Tr::Finite_cells_iterator cit = tr.finite_cells_begin();
+       cit != tr.finite_cells_end(); ++cit)
+  {
+    Cell_handle c = cit;
+    if ( c->subdomain_index() != Subdomain_index()
+         && cell_select(c)
+         && min_dihedral_angle(tr, c) < angle_bound)
+    {
+
+      cells.push_back(c);
+      indices.push_back(c->subdomain_index());
+    }
+  }
+  std::cout << "bad cells : " << cells.size() << std::endl;
+  dump_cells<Tr>(cells, indices, filename);
+}
+
+template<typename Tr>
+void dump_vertices_by_dimension(const Tr& tr, const char* prefix)
+{
+  typedef typename Tr::Vertex_handle Vertex_handle;
+  std::vector< std::vector<Vertex_handle> > vertices_per_dimension(4);
+
+  for (typename Tr::Finite_vertices_iterator
+       vit = tr.finite_vertices_begin();
+       vit != tr.finite_vertices_end();
+       ++vit)
+  {
+    if (vit->in_dimension() == -1)
+      continue;//far point
+    CGAL_assertion(vit->in_dimension() >= 0 && vit->in_dimension() < 4);
+
+    vertices_per_dimension[vit->in_dimension()].push_back(vit);
+  }
+
+  for (int i = 0; i < 4; ++i)
+  {
+    //dimension is i
+    const std::vector<Vertex_handle>& vertices_di = vertices_per_dimension[i];
+
+    std::cout << "Dimension " << i << " : " << vertices_di.size() << std::endl;
+
+    std::ostringstream oss;
+    oss << prefix << "_dimension_" << i << ".off";
+
+    std::ofstream ofs(oss.str());
+    ofs.precision(17);
+    ofs << "OFF" << std::endl;
+    ofs << vertices_di.size() << " 0 0" << std::endl << std::endl;
+
+    for (Vertex_handle vj : vertices_di)
+    {
+      ofs << point(vj->point()) << std::endl;
+    }
+
+    ofs.close();
+  }
+}
+
+template<typename Tr>
+void dump_triangulation_cells(const Tr& tr, const char* filename)
+{
+  std::vector<typename Tr::Cell_handle> cells(tr.number_of_finite_cells());
+  std::vector<typename Tr::Cell::Subdomain_index> indices(tr.number_of_finite_cells());
+  int i = 0;
+  for (typename Tr::Finite_cells_iterator cit = tr.finite_cells_begin();
+       cit != tr.finite_cells_end(); ++cit)
+  {
+    cells[i] = cit;
+    indices[i++] = cit->subdomain_index();
+  }
+  dump_cells<Tr>(cells, indices, filename);
+}
+
+template<typename C3t3>
+void dump_binary(const C3t3& c3t3, const char* filename)
+{
+  std::ofstream os(filename, std::ios::binary | std::ios::out);
+  CGAL::Mesh_3::save_binary_file(os, c3t3);
+  os.close();
+}
+
+template<typename C3t3>
+void dump_medit(const C3t3& c3t3, const char* filename)
+{
+  std::ofstream os(filename, std::ios::out);
+  c3t3.output_to_medit(os, true, true);
+  os.close();
+}
+
+template<typename C3t3>
+void dump_c3t3(const C3t3& c3t3, const char* filename_no_extension)
+{
+  std::string filename_medit(filename_no_extension);
+  filename_medit.append(".mesh");
+  dump_medit(c3t3, filename_medit.c_str());
+
+  std::string filename_binary(filename_no_extension);
+  filename_binary.append(".binary.cgal");
+  dump_binary(c3t3, filename_binary.c_str());
+}
+
+
+} //namespace debug
+} //namespace Tetrahedral_remeshing
+} //namespace CGAL
+
+#endif //CGAL_INTERNAL_TET_REMESHING_HELPERS_H
diff --git a/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h
new file mode 100644
index 00000000000..7ecfff2b82c
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h
@@ -0,0 +1,55 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#include <CGAL/IO/io.h>
+
+#include <iostream>
+#include <fstream>
+
+namespace CGAL
+{
+template<typename T3>
+bool load_triangulation(std::istream& is, T3& t3)
+{
+  std::string s;
+  if (!(is >> s)) return false;
+  bool binary = (s == "binary");
+  if (binary) {
+    if (!(is >> s)) return false;
+  }
+  if (s != "CGAL" || !(is >> s) || s != "c3t3")
+    return false;
+
+  std::getline(is, s);
+  if (binary) CGAL::set_binary_mode(is);
+  else        CGAL::set_ascii_mode(is);
+  is >> t3;
+  return bool(is);
+}
+
+template<typename T3>
+bool save_binary_triangulation(std::ostream& os, const T3& t3)
+{
+  os << "binary CGAL c3t3\n";
+  CGAL::set_binary_mode(os);
+  return !!(os << t3);
+}
+
+template<typename T3>
+bool save_ascii_triangulation(std::ostream& os, const T3& t3)
+{
+  os << "CGAL c3t3\n";
+  CGAL::set_ascii_mode(os);
+  return !!(os << t3);
+}
+
+}
\ No newline at end of file
diff --git a/Tetrahedral_remeshing/include/CGAL/tetrahedral_remeshing.h b/Tetrahedral_remeshing/include/CGAL/tetrahedral_remeshing.h
new file mode 100644
index 00000000000..7877002a0d5
--- /dev/null
+++ b/Tetrahedral_remeshing/include/CGAL/tetrahedral_remeshing.h
@@ -0,0 +1,402 @@
+// Copyright (c) 2020 GeometryFactory (France) and Telecom Paris (France).
+// All rights reserved.
+//
+// This file is part of CGAL (www.cgal.org)
+//
+// $URL$
+// $Id$
+// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
+//
+//
+// Author(s)     : Jane Tournois, Noura Faraj
+
+#ifndef TETRAHEDRAL_REMESHING_H
+#define TETRAHEDRAL_REMESHING_H
+
+#include <CGAL/license/Tetrahedral_remeshing.h>
+
+#include <CGAL/Triangulation_3.h>
+#include <CGAL/Mesh_complex_3_in_triangulation_3.h>
+
+#include <CGAL/Tetrahedral_remeshing/Sizing_field.h>
+#include <CGAL/Tetrahedral_remeshing/Uniform_sizing_field.h>
+#include <CGAL/Tetrahedral_remeshing/internal/tetrahedral_adaptive_remeshing_impl.h>
+#include <CGAL/Tetrahedral_remeshing/internal/compute_c3t3_statistics.h>
+
+#include <CGAL/boost/graph/Named_function_parameters.h>
+#include <CGAL/boost/graph/named_params_helper.h>
+
+#ifdef CGAL_DUMP_REMESHING_STEPS
+#include <sstream>
+#endif
+
+namespace CGAL
+{
+///////////////////////////////////////////////////
+///////////////// TRIANGULATION_3 /////////////////
+///////////////////////////////////////////////////
+/*!
+* \ingroup PkgTetrahedralRemeshingRef
+* remeshes a tetrahedral mesh.
+*
+* It is recommended to use `CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3`
+* for the first parameter, as it inherits from `Triangulation_3` with a `TDS` suitable for this function.
+*
+* This function takes as input a 3-dimensional triangulation
+* and performs a sequence of atomic operations
+* in order to generate as output a high quality mesh with a prescribed
+* uniform density.
+* These atomic operations are performed as follows:
+*   - edge splits, until all edges satisfy a prescribed length criterion,
+*   - edge collapses, until all edges satisfy a prescribed length criterion,
+*   - edge flips, to locally improve dihedral angles, until they can
+*     no longer be improved by flipping,
+*   - global smoothing by vertex relocations,
+*   - re-projection of boundary vertices to the initial surface.
+*
+* This remeshing function can deal with multi-domains, boundaries, and features.
+* It preserves the geometry of
+* subdomains throughout the remeshing process.
+*
+* Subdomains are defined by indices that
+* are stored in the cells of the input triangulation, following the `MeshCellBase_3`
+* concept (refined by `RemeshingCellBase_3`).
+* The surfacic interfaces between subdomains are formed by facets whose two incident cells
+* have different subdomain indices.
+* The edges where three or more subdomains meet form feature polylines,
+* and are considered as constrained edges.
+*
+*
+* @tparam Traits is the geometric traits, model of `RemeshingTriangulationTraits_3`
+* @tparam TDS is the triangulation data structure for `Triangulation_3`,
+*             model of ` TriangulationDataStructure_3`,
+*             with cell base model of `RemeshingCellBase_3`
+*             and vertex base model of `RemeshingVertexBase_3`.
+* @tparam SLDS is an optional parameter for `Triangulation_3`, that
+*             specifies the type of the spatial lock data structure.
+* @tparam NamedParameters a sequence of \ref Remeshing_namedparameters "Named Parameters"
+*
+* @param tr the triangulation to be remeshed, of type `Triangulation_3<Traits, TDS, SLDS>`.
+*           `Remeshing_triangulation` is a helper class that satisfies all the requirements
+*           of its template parameters.
+* @param target_edge_length the uniform target edge length. This parameter provides a
+*          mesh density target for the remeshing algorithm.
+* @param np optional sequence of \ref Remeshing_namedparameters "Named Parameters"
+*          among the ones listed below
+*
+* \cgalNamedParamsBegin
+*  \cgalParamBegin{number_of_iterations} the number of iterations for the full
+*     sequence of atomic operations
+*     performed (listed in the above description)
+*  \cgalParamEnd
+*  \cgalParamBegin{remesh_boundaries} If `false`, none of the input volume boundaries
+*     can be modified.
+*     Otherwise, the topology is preserved, but atomic operations can be performed on the
+*     surfaces, and along feature polylines, such that boundaries are remeshed.
+*  \cgalParamEnd
+*  \cgalParamBegin{edge_is_constrained_map} a property map containing the
+*    constrained - or - not status of each edge of `tr`. A constrained edge can be split
+*    or collapsed, but not flipped.
+*  \cgalParamEnd
+*  \cgalParamBegin{facet_is_constrained_map} a property map containing the
+*    constrained - or - not status of each facet of `tr`. A constrained facet can be split
+*    or collapsed, but not flipped.
+*  \cgalParamEnd
+*  \cgalParamBegin{cell_is_selected_map} a property map containing the
+*    selected - or - not status for each cell of `tr` for remeshing.
+*    Only selected cells are modified (and possibly their neighbors if surfaces are
+*    modified) by remeshing.
+*    By default, all cells with a non-zero `Subdomain_index` are selected.
+*  \cgalParamEnd
+* \cgalNamedParamsEnd
+*
+* \sa `CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3`
+*
+* @todo implement non-uniform sizing field instead of uniform target edge length
+*/
+template<typename Traits, typename TDS, typename SLDS,
+         typename NamedParameters>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Triangulation_3<Traits, TDS, SLDS>& tr,
+  const double& target_edge_length,
+  const NamedParameters& np)
+{
+  typedef CGAL::Triangulation_3<Traits, TDS, SLDS> Triangulation;
+  tetrahedral_isotropic_remeshing(
+    tr,
+    [target_edge_length](const typename Triangulation::Point& /* p */)
+                        {return target_edge_length;},
+    np);
+}
+
+template<typename Traits, typename TDS, typename SLDS,
+         typename NamedParameters>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Triangulation_3<Traits, TDS, SLDS>& tr,
+  const float& target_edge_length,
+  const NamedParameters& np)
+{
+  typedef CGAL::Triangulation_3<Traits, TDS, SLDS> Triangulation;
+  tetrahedral_isotropic_remeshing(
+    tr,
+    [target_edge_length](const typename Triangulation::Point& /* p */)
+                        {return target_edge_length; },
+    np);
+}
+
+template<typename Traits, typename TDS, typename SLDS,
+         typename SizingFunction,
+         typename NamedParameters>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Triangulation_3<Traits, TDS, SLDS>& tr,
+  const SizingFunction& sizing,
+  const NamedParameters& np)
+{
+  CGAL_assertion(tr.is_valid(true));
+
+  typedef CGAL::Triangulation_3<Traits, TDS, SLDS> Tr;
+
+  using parameters::choose_parameter;
+  using parameters::get_parameter;
+
+  bool remesh_surfaces = choose_parameter(get_parameter(np, internal_np::remesh_boundaries),
+                                          true);
+  bool protect = !remesh_surfaces;
+  // bool adaptive = choose_parameter(get_parameter(np, internal_np::adaptive_size),
+  //                              false);
+  std::size_t max_it = choose_parameter(get_parameter(np, internal_np::number_of_iterations),
+                                        1);
+
+  typedef typename internal_np::Lookup_named_param_def <
+    internal_np::cell_selector_t,
+    NamedParameters,
+    Tetrahedral_remeshing::internal::All_cells_selected<Tr>//default
+  > ::type SelectionFunctor;
+  SelectionFunctor cell_select
+    = choose_parameter(get_parameter(np, internal_np::cell_selector),
+                       Tetrahedral_remeshing::internal::All_cells_selected<Tr>());
+
+  typedef std::pair<typename Tr::Vertex_handle, typename Tr::Vertex_handle> Edge_vv;
+  typedef Tetrahedral_remeshing::internal::No_constraint_pmap<Edge_vv> No_edge;
+  typedef typename internal_np::Lookup_named_param_def <
+    internal_np::edge_is_constrained_t,
+    NamedParameters,
+    No_edge//default
+  > ::type ECMap;
+  ECMap ecmap = choose_parameter(get_parameter(np, internal_np::edge_is_constrained),
+                                 No_edge());
+
+  typedef typename Tr::Facet Facet;
+  typedef Tetrahedral_remeshing::internal::No_constraint_pmap<Facet> No_facet;
+  typedef typename internal_np::Lookup_named_param_def <
+    internal_np::facet_is_constrained_t,
+    NamedParameters,
+    No_facet//default
+  > ::type FCMap;
+  FCMap fcmap = choose_parameter(get_parameter(np, internal_np::facet_is_constrained),
+                                 No_facet());
+
+  typedef typename internal_np::Lookup_named_param_def <
+    internal_np::remeshing_visitor_t,
+    NamedParameters,
+    Tetrahedral_remeshing::internal::Default_remeshing_visitor
+  > ::type Visitor;
+  Visitor visitor
+    = choose_parameter(get_parameter(np, internal_np::remeshing_visitor),
+                       Tetrahedral_remeshing::internal::Default_remeshing_visitor());
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "Tetrahedral remeshing ("
+            << "nb_iter = " << max_it << ", "
+            << "protect = " << std::boolalpha << protect
+            << ")" << std::endl;
+
+  std::cout << "Init tetrahedral remeshing...";
+  std::cout.flush();
+#endif
+
+  typedef Tetrahedral_remeshing::internal::Adaptive_remesher<
+    Tr, SizingFunction, ECMap, FCMap, SelectionFunctor, Visitor> Remesher;
+  Remesher remesher(tr, sizing, protect
+                  , ecmap, fcmap
+                  , cell_select
+                  , visitor);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "done." << std::endl;
+  Tetrahedral_remeshing::internal::compute_statistics(
+    remesher.tr(), cell_select, "statistics_begin.txt");
+#endif
+
+  // perform remeshing
+  std::size_t nb_extra_iterations = 3;
+  remesher.remesh(max_it, nb_extra_iterations);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  const double angle_bound = 5.0;
+  Tetrahedral_remeshing::debug::dump_cells_with_small_dihedral_angle(tr,
+    angle_bound, cell_select, "bad_cells.mesh");
+#endif
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  Tetrahedral_remeshing::internal::compute_statistics(tr,
+    cell_select, "statistics_end.txt");
+#endif
+}
+
+template<typename Traits, typename TDS, typename SLDS>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Triangulation_3<Traits, TDS, SLDS>& tr,
+  const double& target_edge_length)
+{
+  tetrahedral_isotropic_remeshing(tr, target_edge_length,
+                                 CGAL::parameters::all_default());
+}
+
+///////////////////////////////////////////////////
+/////// MESH_COMPLEX_3_IN_TRIANGULATION_3 /////////
+///////////////////////////////////////////////////
+
+template<typename Tr,
+         typename CornerIndex, typename CurveIndex,
+         typename NamedParameters>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Mesh_complex_3_in_triangulation_3<Tr, CornerIndex, CurveIndex>& c3t3,
+  const double& target_edge_length,
+  const NamedParameters& np)
+{
+  tetrahedral_isotropic_remeshing(
+    c3t3,
+    [target_edge_length](const typename Tr::Point& /* p */)
+                        {return target_edge_length; },
+    np);
+}
+
+template<typename Tr,
+         typename CornerIndex, typename CurveIndex,
+         typename NamedParameters>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Mesh_complex_3_in_triangulation_3<Tr, CornerIndex, CurveIndex>& c3t3,
+  const float& target_edge_length,
+  const NamedParameters& np)
+{
+  tetrahedral_isotropic_remeshing(
+    c3t3,
+    [target_edge_length](const typename Tr::Point& /*p*/)
+                        {return target_edge_length; },
+    np);
+}
+
+template<typename Tr,
+         typename CornerIndex, typename CurveIndex>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Mesh_complex_3_in_triangulation_3<Tr, CornerIndex, CurveIndex>& c3t3,
+  const double& target_edge_length)
+{
+  return tetrahedral_isotropic_remeshing(c3t3, target_edge_length,
+                                        CGAL::parameters::all_default());
+}
+
+template<typename Tr,
+         typename CornerIndex, typename CurveIndex,
+         typename SizingFunction,
+         typename NamedParameters>
+void tetrahedral_isotropic_remeshing(
+  CGAL::Mesh_complex_3_in_triangulation_3<Tr, CornerIndex, CurveIndex>& c3t3,
+  const SizingFunction& sizing,
+  const NamedParameters& np)
+{
+  CGAL_assertion(c3t3.triangulation().tds().is_valid(true));
+
+  using parameters::get_parameter;
+  using parameters::choose_parameter;
+
+  bool remesh_surfaces = choose_parameter(get_parameter(np, internal_np::remesh_boundaries),
+                                          true);
+  bool protect = !remesh_surfaces;
+  std::size_t max_it = choose_parameter(get_parameter(np, internal_np::number_of_iterations), 1);
+
+  typedef typename internal_np::Lookup_named_param_def <
+  internal_np::cell_selector_t,
+              NamedParameters,
+              Tetrahedral_remeshing::internal::All_cells_selected<Tr>//default
+              > ::type SelectionFunctor;
+  SelectionFunctor cell_select
+    = choose_parameter(get_parameter(np, internal_np::cell_selector),
+                       Tetrahedral_remeshing::internal::All_cells_selected<Tr>());
+
+  typedef std::pair<typename Tr::Vertex_handle, typename Tr::Vertex_handle> Edge_vv;
+  typedef Tetrahedral_remeshing::internal::No_constraint_pmap<Edge_vv> No_edge;
+  typedef typename internal_np::Lookup_named_param_def <
+  internal_np::edge_is_constrained_t,
+              NamedParameters,
+              No_edge//default
+              > ::type ECMap;
+  ECMap ecmap = choose_parameter(get_parameter(np, internal_np::edge_is_constrained),
+                                 No_edge());
+
+  typedef typename Tr::Facet Facet;
+  typedef Tetrahedral_remeshing::internal::No_constraint_pmap<Facet> No_facet;
+  typedef typename internal_np::Lookup_named_param_def <
+  internal_np::facet_is_constrained_t,
+              NamedParameters,
+              No_facet//default
+              > ::type FCMap;
+  FCMap fcmap = choose_parameter(get_parameter(np, internal_np::facet_is_constrained),
+                                 No_facet());
+
+  typedef typename internal_np::Lookup_named_param_def <
+  internal_np::remeshing_visitor_t,
+              NamedParameters,
+              Tetrahedral_remeshing::internal::Default_remeshing_visitor
+              > ::type Visitor;
+  Visitor visitor
+    = choose_parameter(get_parameter(np, internal_np::remeshing_visitor),
+                       Tetrahedral_remeshing::internal::Default_remeshing_visitor());
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "Tetrahedral remeshing ("
+            << "nb_iter = " << max_it << ", "
+            << "protect = " << std::boolalpha << protect
+            << ")" << std::endl;
+
+  std::cout << "Init tetrahedral remeshing...";
+  std::cout.flush();
+#endif
+
+  typedef Tetrahedral_remeshing::internal::Adaptive_remesher<
+  Tr, SizingFunction, ECMap, FCMap, SelectionFunctor,
+  Visitor,
+  CornerIndex, CurveIndex
+  > Remesher;
+  Remesher remesher(c3t3, sizing, protect
+                    , ecmap, fcmap
+                    , cell_select
+                    , visitor);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  std::cout << "done." << std::endl;
+  Tetrahedral_remeshing::internal::compute_statistics(
+    remesher.tr(),
+    cell_select, "statistics_begin.txt");
+#endif
+
+  // perform remeshing
+  std::size_t nb_extra_iterations = 3;
+  remesher.remesh(max_it, nb_extra_iterations);
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_DEBUG
+  const double angle_bound = 5.0;
+  Tetrahedral_remeshing::debug::dump_cells_with_small_dihedral_angle(
+    c3t3.triangulation(),
+    angle_bound, cell_select, "bad_cells.mesh");
+#endif
+#ifdef CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+  Tetrahedral_remeshing::internal::compute_statistics(
+    c3t3.triangulation(),
+    cell_select, "statistics_end.txt");
+#endif
+}
+
+}//end namespace CGAL
+
+#endif //TETRAHEDRAL_REMESHING_H
diff --git a/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/copyright b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/copyright
new file mode 100644
index 00000000000..a49b9cc8d1a
--- /dev/null
+++ b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/copyright
@@ -0,0 +1,2 @@
+GeometryFactory (France)
+Telecom Paris (France)
diff --git a/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/dependencies b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/dependencies
new file mode 100644
index 00000000000..8004efd9b07
--- /dev/null
+++ b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/dependencies
@@ -0,0 +1,31 @@
+Algebraic_foundations
+Arithmetic_kernel
+BGL
+Cartesian_kernel
+Circulator
+Distance_2
+Distance_3
+Filtered_kernel
+Hash_map
+Homogeneous_kernel
+Installation
+Interval_support
+Intersections_2
+Intersections_3
+Kernel_23
+Kernel_d
+Mesh_3
+Modular_arithmetic
+Number_types
+Polygon
+Polygon_mesh_processing
+Profiling_tools
+Property_map
+Random_numbers
+Spatial_sorting
+STL_Extension
+Stream_support
+Tetrahedral_remeshing
+TDS_3
+Triangulation_3
+Union_find
diff --git a/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/license.txt b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/license.txt
new file mode 100644
index 00000000000..8bb8efcb72b
--- /dev/null
+++ b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/license.txt
@@ -0,0 +1 @@
+GPL (v3 or later)
diff --git a/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/maintainer b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/maintainer
new file mode 100644
index 00000000000..dd58aa4afc8
--- /dev/null
+++ b/Tetrahedral_remeshing/package_info/Tetrahedral_remeshing/maintainer
@@ -0,0 +1 @@
+Jane Tournois <jane.tournois@geometryfactory.com>
diff --git a/Tetrahedral_remeshing/test/Tetrahedral_remeshing/CMakeLists.txt b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/CMakeLists.txt
new file mode 100644
index 00000000000..46119c8c74f
--- /dev/null
+++ b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/CMakeLists.txt
@@ -0,0 +1,28 @@
+# Created by the script cgal_create_CMakeLists
+# This is the CMake script for compiling a set of CGAL applications.
+
+cmake_minimum_required(VERSION 3.1...3.14)
+
+project( Tetrahedral_remeshing_Tests )
+
+# CGAL and its components
+find_package( CGAL REQUIRED )
+if ( NOT CGAL_FOUND )
+  message(STATUS "This project requires the CGAL library, and will not be compiled.")
+  return()
+endif()
+
+# Boost and its components
+find_package( Boost REQUIRED )
+if ( NOT Boost_FOUND )
+  message(STATUS "This project requires the Boost library, and will not be compiled.")
+  return()
+endif()
+
+
+# Creating entries for all C++ files with "main" routine
+# ##########################################################
+create_single_source_cgal_program( "test_tetrahedral_remeshing.cpp" )
+create_single_source_cgal_program( "test_tetrahedral_remeshing_with_features.cpp")
+create_single_source_cgal_program( "test_tetrahedral_remeshing_of_one_subdomain.cpp")
+create_single_source_cgal_program( "test_tetrahedral_remeshing_io.cpp")
diff --git a/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing.cpp b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing.cpp
new file mode 100644
index 00000000000..b3341824a82
--- /dev/null
+++ b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing.cpp
@@ -0,0 +1,63 @@
+#define CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+#define CGAL_DUMP_REMESHING_STEPS
+#define CGAL_TETRAHEDRAL_REMESHING_DEBUG
+//#define CGAL_TETRAHEDRAL_REMESHING_GENERATE_INPUT_FILES
+
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+#include <CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h>
+
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <vector>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+template<typename T3>
+void generate_input_one_subdomain(const std::size_t nbv, T3& tr)
+{
+  CGAL::Random rng;
+
+  typedef typename T3::Point Point;
+  std::vector<Point> pts;
+  while (pts.size() < nbv)
+  {
+    const float x = rng.uniform_real(-1.f, 1.f);
+    const float y = rng.uniform_real(-1.f, 1.f);
+    const float z = rng.uniform_real(-1.f, 1.f);
+
+    pts.push_back(Point(x, y, z));
+  }
+  tr.insert(pts.begin(), pts.end());
+
+  for (typename T3::Cell_handle c : tr.finite_cell_handles())
+    c->set_subdomain_index(1);
+
+  CGAL_assertion(tr.is_valid(true));
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_GENERATE_INPUT_FILES
+  std::ofstream out("data/triangulation_one_subdomain.binary.cgal",
+                    std::ios_base::out | std::ios_base::binary);
+  CGAL::save_binary_triangulation(out, tr);
+  out.close();
+#endif
+}
+
+int main(int argc, char* argv[])
+{
+  std::cout << "CGAL Random seed = " << CGAL::get_default_random().get_seed() << std::endl;
+
+  Remeshing_triangulation tr;
+  generate_input_one_subdomain(1000, tr);
+
+  const double target_edge_length = (argc > 1) ? atof(argv[1]) : 0.1;
+
+  CGAL::tetrahedral_isotropic_remeshing(tr, target_edge_length);
+
+  return EXIT_SUCCESS;
+}
diff --git a/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_io.cpp b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_io.cpp
new file mode 100644
index 00000000000..c2cbe1406cc
--- /dev/null
+++ b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_io.cpp
@@ -0,0 +1,78 @@
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+#include <CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h>
+
+#include <CGAL/Random.h>
+
+#include <iostream>
+#include <fstream>
+#include <string>
+#include <vector>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+typedef Remeshing_triangulation::Point          Point;
+typedef Remeshing_triangulation::Cell_handle    Cell_handle;
+
+
+int main(int argc, char* argv[])
+{
+  const unsigned int nbv = (argc > 1) ? atoi(argv[1]) : 100;
+
+  CGAL::Random rng;
+  std::cout << "CGAL Random seed = " << CGAL::get_default_random().get_seed() << std::endl;
+
+  std::vector<Point> points;
+  while (points.size() < nbv)
+  {
+    Point p(rng.get_double(-1., 1.), rng.get_double(-1., 1.), rng.get_double(-1., 1.));
+    points.push_back(p);
+  }
+
+
+  Remeshing_triangulation tr(points.begin(), points.end());
+
+  for (Cell_handle c : tr.finite_cell_handles())
+    c->set_subdomain_index(1);
+
+  std::cout << "save_ascii_triangulation : ";
+  std::cout.flush();
+  std::ofstream out1("remeshing_triangulation.ascii.cgal",
+                     std::ios_base::out);
+  bool ok = CGAL::save_ascii_triangulation(out1, tr);
+  out1.close();
+  assert(ok);
+  std::cout << "done." << std::endl;
+
+  Remeshing_triangulation tr1;
+  std::cout << "load_triangulation (ascii) : ";
+  std::cout.flush();
+  std::ifstream in1("remeshing_triangulation.ascii.cgal",
+                    std::ios_base::in);
+  ok = CGAL::load_triangulation(in1, tr1);
+  assert(ok);
+  std::cout << "done." << std::endl;
+
+  std::cout << "save_binary_triangulation : ";
+  std::cout.flush();
+  std::ofstream out2("remeshing_triangulation.binary.cgal",
+                    std::ios_base::out | std::ios_base::binary);
+  ok = CGAL::save_binary_triangulation(out2, tr);
+  out2.close();
+  assert(ok);
+  std::cout << "done." << std::endl;
+
+  Remeshing_triangulation tr2;
+  std::cout << "load_triangulation (binary) : ";
+  std::cout.flush();
+  std::ifstream in2("remeshing_triangulation.binary.cgal",
+                    std::ios_base::in | std::ios_base::binary);
+  ok = CGAL::load_triangulation(in2, tr2);
+  assert(ok);
+  std::cout << "done." << std::endl;
+
+  return EXIT_SUCCESS;
+}
diff --git a/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_of_one_subdomain.cpp b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_of_one_subdomain.cpp
new file mode 100644
index 00000000000..6133e647b0e
--- /dev/null
+++ b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_of_one_subdomain.cpp
@@ -0,0 +1,81 @@
+#define CGAL_TETRAHEDRAL_REMESHING_GENERATE_INPUT_FILES
+
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+#include <CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h>
+
+#include <CGAL/Random.h>
+
+#include <iostream>
+#include <fstream>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+void generate_input_two_subdomains(const std::size_t nbv, Remeshing_triangulation& tr)
+{
+  CGAL::Random rng;
+
+  typedef Remeshing_triangulation::Point Point;
+  typedef Remeshing_triangulation::Cell_handle Cell_handle;
+
+  while (tr.number_of_vertices() < nbv)
+    tr.insert(Point(rng.get_double(-1., 1.), rng.get_double(-1., 1.), rng.get_double(-1., 1.)));
+
+  const Remeshing_triangulation::Geom_traits::Plane_3
+    plane(Point(0, 0, 0), Point(0, 1, 0), Point(0, 0, 1));
+
+  for (Cell_handle c : tr.finite_cell_handles())
+  {
+    if (plane.has_on_positive_side(
+      CGAL::centroid(c->vertex(0)->point(), c->vertex(1)->point(),
+                     c->vertex(2)->point(), c->vertex(3)->point())))
+      c->set_subdomain_index(1);
+    else
+      c->set_subdomain_index(2);
+  }
+  CGAL_assertion(tr.is_valid(true));
+
+#ifdef CGAL_TETRAHEDRAL_REMESHING_GENERATE_INPUT_FILES
+  std::ofstream os("data/triangulation_two_subdomains.binary.cgal",
+                   std::ios_base::out | std::ios_base::binary);
+  CGAL::save_binary_triangulation(os, tr);
+  os.close();
+#endif
+}
+
+struct Cells_of_subdomain
+{
+private:
+  const int m_subdomain;
+
+public:
+  Cells_of_subdomain(const int& subdomain)
+    : m_subdomain(subdomain)
+  {}
+
+  bool operator()(Remeshing_triangulation::Cell_handle c) const
+  {
+    return m_subdomain == c->subdomain_index();
+  }
+};
+
+int main(int argc, char* argv[])
+{
+  std::cout << "CGAL Random seed = "
+    << CGAL::get_default_random().get_seed() << std::endl;
+
+  const double target_edge_length = (argc > 1) ? atof(argv[1]) : 0.1;
+
+  Remeshing_triangulation tr;
+  generate_input_two_subdomains(1000, tr);
+
+  CGAL::tetrahedral_isotropic_remeshing(tr, target_edge_length,
+      CGAL::parameters::cell_selector(Cells_of_subdomain(2)));
+
+  return EXIT_SUCCESS;
+}
+
diff --git a/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_with_features.cpp b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_with_features.cpp
new file mode 100644
index 00000000000..3ca850d78e6
--- /dev/null
+++ b/Tetrahedral_remeshing/test/Tetrahedral_remeshing/test_tetrahedral_remeshing_with_features.cpp
@@ -0,0 +1,161 @@
+#define CGAL_TETRAHEDRAL_REMESHING_VERBOSE
+#define CGAL_TETRAHEDRAL_REMESHING_GENERATE_INPUT_FILES
+
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/Tetrahedral_remeshing/Remeshing_triangulation_3.h>
+#include <CGAL/tetrahedral_remeshing.h>
+#include <CGAL/Tetrahedral_remeshing/tetrahedral_remeshing_io.h>
+
+#include <CGAL/Random.h>
+#include <CGAL/property_map.h>
+
+#include <boost/unordered_set.hpp>
+
+#include <iostream>
+#include <fstream>
+#include <vector>
+#include <utility>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+
+typedef CGAL::Tetrahedral_remeshing::Remeshing_triangulation_3<K> Remeshing_triangulation;
+
+typedef Remeshing_triangulation::Point         Point;
+typedef Remeshing_triangulation::Vertex_handle Vertex_handle;
+typedef Remeshing_triangulation::Cell_handle   Cell_handle;
+typedef Remeshing_triangulation::Edge          Edge;
+
+class Constrained_edges_property_map
+{
+public:
+  typedef bool                               value_type;
+  typedef bool                               reference;
+  typedef std::pair<Vertex_handle, Vertex_handle> key_type;
+  typedef boost::read_write_property_map_tag category;
+
+private:
+  boost::unordered_set<key_type>* m_set_ptr;
+
+public:
+  Constrained_edges_property_map()
+    : m_set_ptr(NULL)
+  {}
+  Constrained_edges_property_map(boost::unordered_set<key_type>* set_)
+    : m_set_ptr(set_)
+  {}
+
+public:
+  friend void put(Constrained_edges_property_map& map,
+                  const key_type& k,
+                  const bool b)
+  {
+    CGAL_assertion(map.m_set_ptr != NULL);
+    CGAL_assertion(k.first < k.second);
+    if (b)  map.m_set_ptr->insert(k);
+    else    map.m_set_ptr->erase(k);
+  }
+
+  friend value_type get(const Constrained_edges_property_map& map,
+                              const key_type& k)
+  {
+    CGAL_assertion(map.m_set_ptr != NULL);
+    CGAL_assertion(k.first < k.second);
+    return map.m_set_ptr->count(k) > 0;
+  }
+};
+
+void add_edge(Vertex_handle v1,
+              Vertex_handle v2,
+              const Remeshing_triangulation& tr,
+              boost::unordered_set<std::pair<Vertex_handle, Vertex_handle> >& constraints)
+{
+  Cell_handle c;
+  int i, j;
+  if(tr.is_edge(v1, v2, c, i, j))
+    constraints.insert(std::make_pair(v1, v2));
+}
+
+void generate_input_cube(const std::size_t& n,
+              Remeshing_triangulation& tr,
+              boost::unordered_set<std::pair<Vertex_handle, Vertex_handle> >& constraints)
+{
+  CGAL::Random rng;
+
+  // points in a sphere
+  std::vector<Point> pts;
+  while (pts.size() < n)
+    pts.push_back(Point(rng.get_double(-1., 1.), rng.get_double(-1., 1.), rng.get_double(-1., 1.)));
+  tr.insert(pts.begin(), pts.end());
+
+  // vertices of a larger cube
+  Vertex_handle v0 = tr.insert(Point(-2., -2., -2.));
+  Vertex_handle v1 = tr.insert(Point(-2., -2.,  2.));
+
+  Vertex_handle v2 = tr.insert(Point( 2., -2., -2.));
+  Vertex_handle v3 = tr.insert(Point( 2., -2.,  2.));
+
+  Vertex_handle v4 = tr.insert(Point(-2.,  2.,  -2.));
+  Vertex_handle v5 = tr.insert(Point(-2.,  2.,   2.));
+
+  Vertex_handle v6 = tr.insert(Point( 2.,  2., -2.));
+  Vertex_handle v7 = tr.insert(Point( 2.,  2.,  2.));
+
+  CGAL_assertion(tr.is_valid(true));
+
+  // writing file output
+#ifdef CGAL_TETRAHEDRAL_REMESHING_GENERATE_INPUT_FILES
+  std::ofstream outfile("data/sphere_in_cube.tr.cgal",
+                        std::ios_base::out | std::ios_base::binary);
+  CGAL::save_binary_triangulation(outfile, tr);
+  outfile.close();
+#endif
+
+  // constrain cube edges
+  add_edge(v0, v1, tr, constraints);
+  add_edge(v1, v2, tr, constraints);
+  add_edge(v2, v3, tr, constraints);
+  add_edge(v3, v0, tr, constraints);
+
+  add_edge(v4, v5, tr, constraints);
+  add_edge(v5, v6, tr, constraints);
+  add_edge(v6, v7, tr, constraints);
+  add_edge(v7, v4, tr, constraints);
+
+  add_edge(v0, v4, tr, constraints);
+  add_edge(v1, v5, tr, constraints);
+  add_edge(v2, v6, tr, constraints);
+  add_edge(v3, v7, tr, constraints);
+
+  CGAL_assertion(tr.is_valid(true));
+}
+
+void set_subdomain(Remeshing_triangulation& tr, const int index)
+{
+  for (Cell_handle c : tr.finite_cell_handles())
+    c->set_subdomain_index(index);
+}
+
+int main(int argc, char* argv[])
+{
+  CGAL::Random rng;
+  std::cout << "CGAL Random seed = " << CGAL::get_default_random().get_seed() << std::endl;
+
+  Remeshing_triangulation tr;
+  boost::unordered_set<std::pair<Vertex_handle, Vertex_handle> > constraints;
+  generate_input_cube(1000, tr, constraints);
+
+  const double target_edge_length = (argc > 1) ? atof(argv[1]) : 0.02;
+  const int nb_iter = (argc > 2) ? atoi(argv[2]) : 1;
+
+  set_subdomain(tr, 1);
+  assert(tr.is_valid());
+
+  CGAL::tetrahedral_isotropic_remeshing(tr, target_edge_length,
+    CGAL::parameters::edge_is_constrained_map(
+      Constrained_edges_property_map(&constraints))
+    .number_of_iterations(nb_iter));
+
+  return EXIT_SUCCESS;
+}
+
diff --git a/Three/include/CGAL/Three/Scene_group_item.h b/Three/include/CGAL/Three/Scene_group_item.h
index 3f46883a8c7..626e69240ab 100644
--- a/Three/include/CGAL/Three/Scene_group_item.h
+++ b/Three/include/CGAL/Three/Scene_group_item.h
@@ -245,8 +245,12 @@ public Q_SLOTS:
     {
       for(int i = 0; i < children.size(); ++i)
       {
-        if(children[i] >= removed_id)
+        if(children[i] > removed_id)
           --children[i];
+        else if(children[i] == removed_id)//child has been removed from the scene, it doesn't exist anymore.
+        {
+          children.removeAll(removed_id);
+        }
       }
     }
 private:
diff --git a/Triangulation/applications/Triangulation/CMakeLists.txt b/Triangulation/applications/Triangulation/CMakeLists.txt
index d185fab4fdc..1fc7365fd39 100644
--- a/Triangulation/applications/Triangulation/CMakeLists.txt
+++ b/Triangulation/applications/Triangulation/CMakeLists.txt
@@ -26,6 +26,7 @@ if ( NOT Boost_FOUND )
 endif()
 
 find_package(Eigen3 3.1.0)
+include(CGAL_Eigen_support)
 
 # include for local directory
 include_directories( BEFORE include )
@@ -36,8 +37,6 @@ include_directories( BEFORE include )
 # ##########################################################
 
 create_single_source_cgal_program( "points_to_RT_to_off.cpp" )
-CGAL_target_use_Eigen(points_to_RT_to_off)
+target_link_libraries(points_to_RT_to_off PUBLIC CGAL::Eigen_support)
 create_single_source_cgal_program( "points_to_DT_to_off.cpp" )
-CGAL_target_use_Eigen(points_to_DT_to_off)
-
-
+target_link_libraries(points_to_DT_to_off PUBLIC CGAL::Eigen_support)
diff --git a/Triangulation/benchmark/Triangulation/CMakeLists.txt b/Triangulation/benchmark/Triangulation/CMakeLists.txt
index 0e03f970220..681ffd10bc0 100644
--- a/Triangulation/benchmark/Triangulation/CMakeLists.txt
+++ b/Triangulation/benchmark/Triangulation/CMakeLists.txt
@@ -14,12 +14,13 @@ if ( CGAL_FOUND )
   include(${CGAL_USE_FILE})
 
   find_package(Eigen3 3.1.0)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     include_directories (BEFORE "include")
     create_single_source_cgal_program( "delaunay.cpp" )
-    CGAL_target_use_Eigen(delaunay)
+    target_link_libraries(delaunay PUBLIC CGAL::Eigen_support)
     create_single_source_cgal_program( "Td_vs_T2_and_T3.cpp" )
-    CGAL_target_use_Eigen(Td_vs_T2_and_T3)
+    target_link_libraries(Td_vs_T2_and_T3 PUBLIC CGAL::Eigen_support)
 
   else()
     message(STATUS "NOTICE: Some of the executables in this directory need Eigen 3.1 (or greater) and will not be compiled.")
@@ -28,4 +29,3 @@ if ( CGAL_FOUND )
 else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 endif()
-
diff --git a/Triangulation/doc/Triangulation/Concepts/TriangulationDSFullCell.h b/Triangulation/doc/Triangulation/Concepts/TriangulationDSFullCell.h
index 5d38a4e9cf9..3c32f97f7c5 100644
--- a/Triangulation/doc/Triangulation/Concepts/TriangulationDSFullCell.h
+++ b/Triangulation/doc/Triangulation/Concepts/TriangulationDSFullCell.h
@@ -107,7 +107,7 @@ void * for_compact_container() const;
 /*!
 
 */
-void * & for_compact_container();
+void for_compact_container(void *p);
 
 /// @}
 
diff --git a/Triangulation/doc/Triangulation/Concepts/TriangulationDSVertex.h b/Triangulation/doc/Triangulation/Concepts/TriangulationDSVertex.h
index 2ef050f82fe..5e3def7d9bd 100644
--- a/Triangulation/doc/Triangulation/Concepts/TriangulationDSVertex.h
+++ b/Triangulation/doc/Triangulation/Concepts/TriangulationDSVertex.h
@@ -106,7 +106,7 @@ void * for_compact_container() const;
 /*!
 
 */
-void * & for_compact_container();
+void for_compact_container(void *p);
 
 /// @}
 
diff --git a/Triangulation/examples/Triangulation/CMakeLists.txt b/Triangulation/examples/Triangulation/CMakeLists.txt
index 7f8609612df..f6589b3e63a 100644
--- a/Triangulation/examples/Triangulation/CMakeLists.txt
+++ b/Triangulation/examples/Triangulation/CMakeLists.txt
@@ -17,7 +17,8 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.1.0)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     create_single_source_cgal_program( "barycentric_subdivision.cpp" )
     create_single_source_cgal_program( "delaunay_triangulation.cpp" )
     create_single_source_cgal_program( "convex_hull.cpp" )
@@ -34,7 +35,7 @@ if ( CGAL_FOUND )
         triangulation
         triangulation_data_structure_dynamic
         triangulation_data_structure_static)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endforeach()
   else()
     message(STATUS "NOTICE: Some of the executables in this directory need Eigen 3.1 (or greater) and will not be compiled.")
@@ -45,4 +46,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Triangulation/include/CGAL/TDS_full_cell_default_storage_policy.h b/Triangulation/include/CGAL/TDS_full_cell_default_storage_policy.h
index d5f0735c8e8..3b6508f6017 100644
--- a/Triangulation/include/CGAL/TDS_full_cell_default_storage_policy.h
+++ b/Triangulation/include/CGAL/TDS_full_cell_default_storage_policy.h
@@ -44,7 +44,7 @@ struct TFC_data< Vertex_handle, Full_cell_handle, Dimen, TDS_full_cell_default_s
     : vertices_(dmax+1), neighbors_(dmax+1)
     {}
     void*   for_compact_container() const { return vertices_.for_compact_container(); }
-    void* & for_compact_container()       { return vertices_.for_compact_container(); }
+    void    for_compact_container(void *p){ vertices_.for_compact_container(p); }
     int dimension() const { return ( vertices_.size() - 1 ); }
     void set_mirror_index(const int, const int) {}
 #ifdef BOOST_NO_INT64_T
diff --git a/Triangulation/include/CGAL/Triangulation_ds_full_cell.h b/Triangulation/include/CGAL/Triangulation_ds_full_cell.h
index 125cc2e443f..83b48a441d5 100644
--- a/Triangulation/include/CGAL/Triangulation_ds_full_cell.h
+++ b/Triangulation/include/CGAL/Triangulation_ds_full_cell.h
@@ -204,7 +204,7 @@ public:
     TDS_data & tds_data() { return tds_data_; } /* Concept */
 
     void*   for_compact_container() const { return combinatorics_.for_compact_container(); }
-    void* & for_compact_container() { return combinatorics_.for_compact_container(); }
+    void    for_compact_container(void* p){ combinatorics_.for_compact_container(p); }
 
     bool is_valid(bool verbose = false, int = 0) const /* Concept */
     {
diff --git a/Triangulation/include/CGAL/Triangulation_ds_vertex.h b/Triangulation/include/CGAL/Triangulation_ds_vertex.h
index c6528a1231d..aaa1e2067fc 100644
--- a/Triangulation/include/CGAL/Triangulation_ds_vertex.h
+++ b/Triangulation/include/CGAL/Triangulation_ds_vertex.h
@@ -102,7 +102,7 @@ public:
 public: // FOR MEMORY MANAGEMENT
 
     void*   for_compact_container() const { return full_cell_.for_compact_container(); }
-    void* & for_compact_container()       { return full_cell_.for_compact_container(); }
+    void    for_compact_container(void *p){ full_cell_.for_compact_container(p); }
 
 };  // end of Triangulation_ds_vertex
 
diff --git a/Triangulation/include/CGAL/internal/Static_or_dynamic_array.h b/Triangulation/include/CGAL/internal/Static_or_dynamic_array.h
index f198464e874..54fca5abaea 100644
--- a/Triangulation/include/CGAL/internal/Static_or_dynamic_array.h
+++ b/Triangulation/include/CGAL/internal/Static_or_dynamic_array.h
@@ -66,9 +66,9 @@ struct S_or_D_array< Containee, Dimension_tag< D >, WithCompactContainerHelper >
     {
         return (*this)[0].for_compact_container();
     }
-    void* & for_compact_container()
+    void    for_compact_container(void *p)
     {
-        return (*this)[0].for_compact_container();
+        (*this)[0].for_compact_container(p);
     }
 };
 
@@ -101,7 +101,7 @@ struct S_or_D_array< Containee, Dynamic_dimension_tag, true >
     {}
     void* fcc_;
     void*   for_compact_container() const { return fcc_; }
-    void* & for_compact_container()       { return fcc_; }
+    void    for_compact_container(void* p)       { fcc_ = p; }
 };
 
 } // end of namespace internal
diff --git a/Triangulation/test/Triangulation/CMakeLists.txt b/Triangulation/test/Triangulation/CMakeLists.txt
index 2aed902c338..8dd9796ba23 100644
--- a/Triangulation/test/Triangulation/CMakeLists.txt
+++ b/Triangulation/test/Triangulation/CMakeLists.txt
@@ -15,7 +15,8 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package(Eigen3 3.1.0)
-  if (EIGEN3_FOUND)
+  include(CGAL_Eigen_support)
+  if (TARGET CGAL::Eigen_support)
     include_directories (BEFORE "include")
 
     create_single_source_cgal_program( "test_triangulation.cpp" )
@@ -31,7 +32,7 @@ if ( CGAL_FOUND )
         test_tds
         test_torture
         test_insert_if_in_star)
-      CGAL_target_use_Eigen(${target})
+      target_link_libraries(${target} PUBLIC CGAL::Eigen_support)
     endforeach()
 
   else()
@@ -41,4 +42,3 @@ if ( CGAL_FOUND )
 else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 endif()
-
diff --git a/Triangulation_2/doc/Triangulation_2/Triangulation_2.txt b/Triangulation_2/doc/Triangulation_2/Triangulation_2.txt
index 90446677a4c..009f3845620 100644
--- a/Triangulation_2/doc/Triangulation_2/Triangulation_2.txt
+++ b/Triangulation_2/doc/Triangulation_2/Triangulation_2.txt
@@ -152,6 +152,17 @@ Therefore, each edge of the triangulation
 is incident to exactly two faces
 and the set of faces of a triangulation is topologically
 equivalent to a two-dimensional sphere.
+
+Note that
+the *infinite vertex* has no significant
+coordinates and that no geometric predicate can be applied on it
+nor on an infinite face.
+
+\cgalFigureBegin{Triangulation_2D_Fig_infinite_vertex,infinite.png}
+Infinite vertex and infinite faces
+\cgalFigureEnd
+
+
 This extends to lower dimensional triangulations
 arising in degenerate cases or when the triangulations
 as less than three vertices.
@@ -162,16 +173,15 @@ topologically equivalent to a \f$ 1\f$-sphere.
 A zero dimensional triangulation, whose domain is reduced to a
 single point, is represented by two vertices that is
 topologically equivalent to a \f$ 0\f$-sphere.
+This is illustrated in \cgalFigureRef{Triangulation_2D_Fig_low_dimensional}
+and the example \ref Triangulation_2/low_dimensional.cpp
+shows how to traverse a low dimensional triangulation.
 
-Note that
-the *infinite vertex* has no significant
-coordinates and that no geometric predicate can be applied on it
-nor on an infinite face.
-
-\cgalFigureBegin{Triangulation_2D_Fig_infinite_vertex,infinite.png}
-Infinite vertex and infinite faces
+\cgalFigureBegin{Triangulation_2D_Fig_low_dimensional,low_dimensional.svg}
+Triangulations with zero, one, and two finite vertices.
 \cgalFigureEnd
 
+
 \subsection Triangulation_2ARepresentationBasedonFaces A Representation Based on Faces and Vertices
 
 Because a triangulation is a set of
@@ -1355,4 +1365,3 @@ Julia Fl&ouml;totto, Monique Teillaud and Mariette Yvinec.
 
 */
 } /* namespace CGAL */
-
diff --git a/Triangulation_2/doc/Triangulation_2/examples.txt b/Triangulation_2/doc/Triangulation_2/examples.txt
index 7061593de13..459982e56a2 100644
--- a/Triangulation_2/doc/Triangulation_2/examples.txt
+++ b/Triangulation_2/doc/Triangulation_2/examples.txt
@@ -21,4 +21,5 @@
 \example Triangulation_2/polylines_triangulation.cpp
 \example Triangulation_2/segment_soup_to_polylines.cpp
 \example Triangulation_2/draw_triangulation_2.cpp
+\example Triangulation_2/low_dimensional.cpp
 */
diff --git a/Triangulation_2/doc/Triangulation_2/fig/low_dimensional.svg b/Triangulation_2/doc/Triangulation_2/fig/low_dimensional.svg
new file mode 100644
index 00000000000..147a847ec47
Binary files /dev/null and b/Triangulation_2/doc/Triangulation_2/fig/low_dimensional.svg differ
diff --git a/Triangulation_2/examples/Triangulation_2/low_dimensional.cpp b/Triangulation_2/examples/Triangulation_2/low_dimensional.cpp
new file mode 100644
index 00000000000..fed87295eb0
--- /dev/null
+++ b/Triangulation_2/examples/Triangulation_2/low_dimensional.cpp
@@ -0,0 +1,74 @@
+#include <iostream>
+
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+#include <CGAL/Triangulation_2.h>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel K;
+typedef CGAL::Triangulation_2<K>          Triangulation;
+typedef Triangulation::Vertex_handle      Vertex_handle;
+typedef Triangulation::Face_handle        Face_handle;
+typedef Triangulation::All_faces_iterator All_faces_iterator;
+typedef Triangulation::All_edges_iterator All_edges_iterator;
+typedef Triangulation::Point              Point;
+
+int main() {
+
+  Point p(0,0), q(1,0);
+
+  Triangulation t;
+
+  Vertex_handle inf = t.infinite_vertex();
+  Face_handle fh = inf->face();
+  assert(fh->vertex(0) == inf);
+  assert(fh->vertex(1) == Vertex_handle());
+  assert(fh->vertex(2) == Vertex_handle());
+
+  assert(t.all_faces_begin() == t.all_faces_end());
+  assert(t.all_edges_begin() == t.all_edges_end());
+
+  t.insert(p);
+  Vertex_handle pvh = t.finite_vertices_begin();
+  Face_handle pfh = pvh->face();
+  assert(pfh->neighbor(0) == fh);
+
+  t.insert(q);
+
+  assert(t.infinite_vertex()->face() == fh);
+
+  assert( (fh->vertex(0) == inf) || (fh->vertex(1) == inf) );
+
+  std::cout << "After the insertion of the second point" <<std::endl;
+  std::cout << "|V| = " << t.number_of_vertices() << std::endl;
+  std::cout << "|F| = " << t.number_of_faces() << std::endl;
+
+
+  // Even now we have not really faces
+  assert(t.all_faces_begin() == t.all_faces_end());
+
+  for (Triangulation::All_edges_iterator it = t.all_edges_begin();
+      it != t.all_edges_end();  ++it) {
+    Face_handle fh = it->first;
+    Vertex_handle v0 = fh->vertex(0);
+    Vertex_handle v1 = fh->vertex(1);
+    std::cout << "Edge: ";
+    if (v0 == inf) {std::cout << "inf -- ";}else{ std::cout<< v0->point() << " -- ";}
+    if (v1 == inf) {std::cout << "inf\n";}else{ std::cout<< v1->point() << std::endl;}
+  }
+
+  std::cout << "Edge traversal by hand" << std::endl;
+  Face_handle done = fh;
+  do {
+      assert(fh->vertex(2) == Vertex_handle());
+      assert(fh->neighbor(2) == Face_handle());
+      Vertex_handle v0 = fh->vertex(0);
+      Vertex_handle v1 = fh->vertex(1);
+      std::cout << "Edge: ";
+      if (v0 == inf) {std::cout << "inf -- ";}else{ std::cout<< v0->point() << " -- ";}
+      if (v1 == inf) {std::cout << "inf\n";}else{ std::cout<< v1->point() << std::endl;}
+      fh = fh->neighbor(0);
+  } while (fh != done);
+
+  std::cout << std::endl;
+
+  return 0;
+}
diff --git a/Triangulation_2/include/CGAL/Constrained_Delaunay_triangulation_2.h b/Triangulation_2/include/CGAL/Constrained_Delaunay_triangulation_2.h
index c5964f87ac2..e925bb4d102 100644
--- a/Triangulation_2/include/CGAL/Constrained_Delaunay_triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Constrained_Delaunay_triangulation_2.h
@@ -179,6 +179,19 @@ public:
   virtual ~Constrained_Delaunay_triangulation_2() {}
 
 
+  // Ensure rule-of-five: define the copy- and move- constructors
+  // as well as the copy- and move- assignment operators.
+  Constrained_Delaunay_triangulation_2(
+      const Constrained_Delaunay_triangulation_2 &) = default;
+  Constrained_Delaunay_triangulation_2(
+      Constrained_Delaunay_triangulation_2 &&) = default;
+
+  Constrained_Delaunay_triangulation_2 &
+  operator=(const Constrained_Delaunay_triangulation_2 &) = default;
+
+  Constrained_Delaunay_triangulation_2 &
+  operator=(Constrained_Delaunay_triangulation_2 &&) = default;
+
   // FLIPS
   bool is_flipable(Face_handle f, int i, bool perturb = true) const;
   void flip(Face_handle& f, int i);
diff --git a/Triangulation_2/include/CGAL/Constrained_triangulation_2.h b/Triangulation_2/include/CGAL/Constrained_triangulation_2.h
index 272aec6a330..bbb45c02a46 100644
--- a/Triangulation_2/include/CGAL/Constrained_triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Constrained_triangulation_2.h
@@ -51,6 +51,25 @@ struct CGAL_DEPRECATED No_intersection_tag :
 
 namespace internal {
 
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  struct Indentation_level {
+    int n;
+    Indentation_level() : n(0) {}
+    friend std::ostream& operator<<(std::ostream& os, Indentation_level level) {
+      return os << std::string(2*level.n, ' ');
+    }
+    Indentation_level& operator++() { ++n; return *this; }
+    Indentation_level& operator--() { --n; return *this; }
+    struct Exit_guard {
+      Exit_guard(Indentation_level& level): level(level) { ++level; }
+      Exit_guard(const Exit_guard& other) : level(other.level) { ++level; }
+      Indentation_level& level;
+      ~Exit_guard() { --level; }
+    };
+    Exit_guard open_new_scope() { return Exit_guard(*this); }
+  } cdt_2_indent_level;
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
+
 template <typename K>
 struct Itag {
   typedef typename boost::mpl::if_<typename Algebraic_structure_traits<typename K::FT>::Is_exact,
@@ -87,6 +106,7 @@ public:
   typedef typename Triangulation::size_type size_type;
   typedef typename Triangulation::Locate_type Locate_type;
   typedef typename Triangulation::All_faces_iterator All_faces_iterator;
+  typedef typename Triangulation::Finite_edges_iterator Finite_edges_iterator;
   typedef typename Triangulation::Face_circulator Face_circulator;
   typedef typename Triangulation::Edge_circulator Edge_circulator;
   typedef typename Triangulation::Vertex_circulator Vertex_circulator;
@@ -129,6 +149,8 @@ public:
   using Triangulation::geom_traits;
   using Triangulation::all_faces_begin;
   using Triangulation::all_faces_end;
+  using Triangulation::finite_edges_begin;
+  using Triangulation::finite_edges_end;
   using Triangulation::side_of_oriented_circle;
   using Triangulation::is_infinite;
   using Triangulation::collinear_between;
@@ -148,6 +170,7 @@ public:
   using Triangulation::all_edges_begin;
   using Triangulation::all_edges_end;
   using Triangulation::mirror_index;
+  using Triangulation::mirror_edge;
   using Triangulation::orientation;
 #endif
 
@@ -197,6 +220,17 @@ public:
   //TODO Is that destructor correct ?
   virtual ~Constrained_triangulation_2() {}
 
+  // Ensure rule-of-five: define the copy- and move- constructors
+  // as well as the copy- and move- assignment operators.
+  Constrained_triangulation_2(const Constrained_triangulation_2 &) = default;
+  Constrained_triangulation_2(Constrained_triangulation_2 &&) = default;
+
+  Constrained_triangulation_2 &
+  operator=(const Constrained_triangulation_2 &) = default;
+
+  Constrained_triangulation_2 &
+  operator=(Constrained_triangulation_2 &&) = default;
+
 
   Constrained_edges_iterator constrained_edges_begin() const
   {
@@ -537,7 +571,7 @@ public:
     {
       Edge_circulator ec=incident_edges(v), done(ec);
       bool are_there = false;
-      if (ec == 0) return are_there;
+      if (ec == nullptr) return are_there;
       do {
         if(is_constrained(*ec)) {
           *out++ = *ec;
@@ -553,7 +587,7 @@ public:
  OutputItEdges  incident_constraints(Vertex_handle v,
                                       OutputItEdges out) const {
    Edge_circulator ec=incident_edges(v), done(ec);
-   if (ec == 0) return  out;
+   if (ec == nullptr) return  out;
    do {
      if(is_constrained(*ec))    *out++ = *ec;
      ec++;
@@ -656,6 +690,19 @@ insert(const Point& a, Locate_type lt, Face_handle loc, int li)
   Vertex_handle v1, v2;
   bool insert_in_constrained_edge = false;
 
+  std::list<std::pair<Vertex_handle,Vertex_handle> > constrained_edges;
+  bool one_dimensional = false;
+  if(dimension() == 1){
+    one_dimensional = true;
+    for(Finite_edges_iterator it = finite_edges_begin();
+        it != finite_edges_end();
+        ++it){
+      if(is_constrained(*it)){
+        constrained_edges.emplace_back(it->first->vertex(cw(it->second)),
+                                       it->first->vertex(ccw(it->second)));
+      }
+    }
+  }
   if ( lt == Triangulation::EDGE && loc->is_constrained(li) )
   {
     if(boost::is_same<Itag, No_constraint_intersection_tag>::value)
@@ -668,6 +715,18 @@ insert(const Point& a, Locate_type lt, Face_handle loc, int li)
 
   va = Triangulation::insert(a,lt,loc,li);
 
+  if(one_dimensional && (dimension() == 2)){
+    for(const std::pair<Vertex_handle,Vertex_handle>& vp : constrained_edges){
+      Face_handle fh;
+      int i;
+      if(this->is_edge(vp.first, vp.second, fh,i)){
+        fh->set_constraint(i,true);
+        boost::tie(fh,i) = mirror_edge(Edge(fh,i));
+        fh->set_constraint(i,true);
+      }
+    }
+  }
+
   if (insert_in_constrained_edge)
     update_constraints_incident(va, v1,v2);
   else if(lt != Triangulation::VERTEX)
@@ -728,10 +787,25 @@ insert_constraint(Vertex_handle  vaa, Vertex_handle vbb)
   std::stack<std::pair<Vertex_handle, Vertex_handle> > stack;
   stack.push(std::make_pair(vaa,vbb));
 
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::insert_constraint( #" << vaa->time_stamp() << "= " << vaa->point()
+            << " , #" << vbb->time_stamp() << "= " << vbb->point()
+            << " )\n";
+  internal::Indentation_level::Exit_guard exit_guard = CGAL::internal::cdt_2_indent_level.open_new_scope();
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
   while(! stack.empty()){
     boost::tie(vaa,vbb) = stack.top();
     stack.pop();
     CGAL_triangulation_precondition( vaa != vbb);
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+    std::cerr << CGAL::internal::cdt_2_indent_level
+              << "CT_2::insert_constraint, stack pop=( #" << vaa->time_stamp() << "= " << vaa->point()
+              << " , #" << vbb->time_stamp() << "= " << vbb->point()
+              << " ) remaining stack size: "
+              << stack.size() << '\n';
+    CGAL_assertion(this->is_valid());
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
     Vertex_handle vi;
 
     Face_handle fr;
@@ -767,10 +841,26 @@ insert_constraint(Vertex_handle  vaa, Vertex_handle vbb)
                                                  vi);
     if ( intersection) {
       if (vi != vaa && vi != vbb) {
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::insert_constraint stask push [vaa, vi] ( #" << vaa->time_stamp() << "= " << vaa->point()
+            << " , #" << vi->time_stamp() << "= " << vi->point()
+            << " )\n";
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::insert_constraint stask push [vi, vbb] ( #" << vi->time_stamp() << "= " << vi->point()
+            << " , #" << vbb->time_stamp() << "= " << vbb->point()
+            << " )\n";
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
         stack.push(std::make_pair(vaa,vi));
         stack.push(std::make_pair(vi,vbb));
       }
       else{
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::insert_constraint stask push [vaa, vbb]( #" << vaa->time_stamp() << "= " << vaa->point()
+            << " , #" << vbb->time_stamp() << "= " << vbb->point()
+            << " )\n";
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
         stack.push(std::make_pair(vaa,vbb));
       }
       continue;
@@ -814,6 +904,30 @@ find_intersected_faces(Vertex_handle vaa,
 
   // to deal with the case where the first crossed edge
   // is constrained
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::find_intersected_faces ( #" << vaa->time_stamp() << "= " << vaa->point()
+            << " , #" << vbb->time_stamp() << "= " << vbb->point()
+            << " )\n"
+            << CGAL::internal::cdt_2_indent_level
+            << "> current constrained edges are:\n";
+  for(Constrained_edges_iterator edge_it = this->constrained_edges_begin(),
+        end = this->constrained_edges_end();
+      edge_it != end; ++edge_it)
+  {
+    std::cerr <<CGAL::internal::cdt_2_indent_level
+              << "> (#"
+              << edge_it->first->vertex(cw(edge_it->second))->time_stamp()
+              << ", #"
+              << edge_it->first->vertex(ccw(edge_it->second))->time_stamp()
+              << ")\n";
+  }
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "> current face is ( #" << current_face->vertex(0)->time_stamp()
+            << " #" << current_face->vertex(1)->time_stamp()
+            << " #" << current_face->vertex(2)->time_stamp() << " )\n";
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
+
   if(current_face->is_constrained(ind)) {
     vi=intersect(current_face, ind, vaa, vbb);
     return true;
@@ -971,14 +1085,22 @@ intersect(Face_handle f, int i,
   const Point& pc = vcc->point();
   const Point& pd = vdd->point();
 
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::intersect segment ( #" << vaa->time_stamp() << "= " << vaa->point()
+            << " , #" << vbb->time_stamp() << "= " << vbb->point()
+            << " ) with edge ( #"<< vcc->time_stamp() << "= " << vcc->point()
+            << " , #" << vdd->time_stamp() << "= " << vdd->point()
+            << " )\n";
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
   Point pi; //creator for point is required here
   Itag itag = Itag();
   bool ok  = intersection(geom_traits(), pa, pb, pc, pd, pi, itag );
 
   Vertex_handle vi;
   if ( !ok) {  //intersection detected but not computed
-    int i = limit_intersection(geom_traits(), pa, pb, pc, pd, itag);
-    switch(i){
+    int int_index = limit_intersection(geom_traits(), pa, pb, pc, pd, itag);
+    switch(int_index){
     case 0 : vi = vaa; break;
     case 1 : vi = vbb; break;
     case 2 : vi = vcc; break;
@@ -992,6 +1114,11 @@ intersect(Face_handle f, int i,
     remove_constrained_edge(f, i);
     vi = virtual_insert(pi, f);
   }
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::intersect, `vi` is ( #" << vi->time_stamp() << "= " << vi->point()
+            << " )\n";
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
 
   // vi == vc or vi == vd may happen even if intersection==true
   // due to approximate construction of the intersection
@@ -1045,7 +1172,7 @@ update_constraints_incident(Vertex_handle va,
     //dimension() ==2
     int cwi, ccwi, indf;
     Face_circulator fc=incident_faces(va), done(fc);
-    CGAL_triangulation_assertion(fc != 0);
+    CGAL_triangulation_assertion(fc != nullptr);
     do {
       indf = fc->index(va);
       cwi=cw(indf);
@@ -1072,7 +1199,7 @@ clear_constraints_incident(Vertex_handle va)
  Edge_circulator ec=incident_edges(va), done(ec);
  Face_handle f;
  int indf;
-  if ( ec != 0){
+  if ( ec != nullptr){
     do {
       f = (*ec).first ;
       indf = (*ec).second;
@@ -1247,6 +1374,14 @@ void
 Constrained_triangulation_2<Gt,Tds,Itag>::
 remove_constrained_edge(Face_handle f, int i)
 {
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  std::cerr << CGAL::internal::cdt_2_indent_level
+            << "CT_2::remove_constrained_edge ( #"
+            << f->vertex(cw(i))->time_stamp()
+            << ", #"
+            << f->vertex(ccw(i))->time_stamp()
+            << ")\n";
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
   f->set_constraint(i, false);
   if (dimension() == 2)
     (f->neighbor(i))->set_constraint(mirror_index(f,i), false);
@@ -1259,7 +1394,7 @@ Constrained_triangulation_2<Gt,Tds,Itag>::
 remove_incident_constraints(Vertex_handle v)
 {
    Edge_circulator ec=incident_edges(v), done(ec);
-   if (ec == 0) return;
+   if (ec == nullptr) return;
    do {
         if(is_constrained(*ec)) { remove_constrained_edge((*ec).first,
                                                    (*ec).second);}
@@ -1518,7 +1653,8 @@ intersection(const Gt& gt,
   if(!result) return result;
   if(pi == pa || pi == pb || pi == pc || pi == pd) {
 #ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
-    std::cerr << "  CT_2::intersection: intersection is an existing point "
+    std::cerr << CGAL::internal::cdt_2_indent_level
+              << "  CT_2::intersection: intersection is an existing point "
               << pi << std::endl;
 #endif
     return result;
@@ -1540,7 +1676,8 @@ intersection(const Gt& gt,
   if(do_overlap(bb, bbox(pd))) pi = pd;
 #ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
   if(pi == pa || pi == pb || pi == pc || pi == pd) {
-    std::cerr << "  CT_2::intersection: intersection SNAPPED to an existing point "
+    std::cerr << CGAL::internal::cdt_2_indent_level
+              << "  CT_2::intersection: intersection SNAPPED to an existing point "
               << pi << std::endl;
   }
 #endif
@@ -1578,6 +1715,17 @@ compute_intersection(const Gt& gt,
     construct_segment=gt.construct_segment_2_object();
   Object result = compute_intersec(construct_segment(pa,pb),
                                    construct_segment(pc,pd));
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+  typename Gt::Segment_2 s;
+  if(assign(s, result)) {
+    std::cerr << CGAL::internal::cdt_2_indent_level
+              << "compute_intersection: " << s << '\n';
+  }
+  if(assign(pi, result)) {
+    std::cerr << CGAL::internal::cdt_2_indent_level
+              << "compute_intersection: " << pi << '\n';
+  }
+#endif // CGAL_CDT_2_DEBUG_INTERSECTIONS
   return assign(pi, result);
 }
 
diff --git a/Triangulation_2/include/CGAL/Constrained_triangulation_plus_2.h b/Triangulation_2/include/CGAL/Constrained_triangulation_plus_2.h
index 0b19a9a5698..ac7f401174a 100644
--- a/Triangulation_2/include/CGAL/Constrained_triangulation_plus_2.h
+++ b/Triangulation_2/include/CGAL/Constrained_triangulation_plus_2.h
@@ -217,6 +217,8 @@ public:
     , hierarchy(Vh_less_xy(this))
   { copy_triangulation(ctp);}
 
+  Constrained_triangulation_plus_2(Constrained_triangulation_plus_2&&) = default;
+
   virtual ~Constrained_triangulation_plus_2() {}
 
   Constrained_triangulation_plus_2 & operator=(const Constrained_triangulation_plus_2& ctp)
@@ -225,6 +227,8 @@ public:
     return *this;
   }
 
+  Constrained_triangulation_plus_2& operator=(Constrained_triangulation_plus_2&&) = default;
+
   template<class InputIterator>
   Constrained_triangulation_plus_2(InputIterator first,
                                    InputIterator last,
@@ -415,7 +419,7 @@ public:
     ++beg;
     Face_container<Constrained_triangulation_plus_2> fc(*this);
 
-    Constraint_id head = 0, tail = 0;
+    Constraint_id head = nullptr, tail = nullptr;
     if(pos != beg){
       // split off head
       --pos;
@@ -496,7 +500,7 @@ public:
       return pos;
 
     }
-    Constraint_id head = 0, tail = 0;
+    Constraint_id head = nullptr, tail = nullptr;
     Vertices_in_constraint_iterator bit = vertices_in_constraint_begin(cid);
     Vertices_in_constraint_iterator pred = pos;
     --pred;
diff --git a/Triangulation_2/include/CGAL/Delaunay_triangulation_2.h b/Triangulation_2/include/CGAL/Delaunay_triangulation_2.h
index b45bcb11f40..c8fc845f01b 100644
--- a/Triangulation_2/include/CGAL/Delaunay_triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Delaunay_triangulation_2.h
@@ -90,6 +90,11 @@ public:
        : Triangulation_2<Gt,Tds>(tr)
   {   CGAL_triangulation_postcondition(is_valid());  }
 
+  Delaunay_triangulation_2(Delaunay_triangulation_2&&) = default;
+  Delaunay_triangulation_2& operator=(const Delaunay_triangulation_2&) = default;
+  Delaunay_triangulation_2& operator=(Delaunay_triangulation_2&&) = default;
+  ~Delaunay_triangulation_2() = default;
+
  template <class InputIterator>
  Delaunay_triangulation_2(InputIterator first, InputIterator last,
                           const Gt& gt = Gt())
diff --git a/Triangulation_2/include/CGAL/Triangulation_2.h b/Triangulation_2/include/CGAL/Triangulation_2.h
index 34b7968a10f..3f73f238eae 100644
--- a/Triangulation_2/include/CGAL/Triangulation_2.h
+++ b/Triangulation_2/include/CGAL/Triangulation_2.h
@@ -242,6 +242,7 @@ public:
   // CONSTRUCTORS
   Triangulation_2(const Geom_traits& geom_traits=Geom_traits());
   Triangulation_2(const Triangulation_2<Gt,Tds> &tr);
+  Triangulation_2(Triangulation_2&&) = default;
 
   template <class InputIterator>
   Triangulation_2(InputIterator first, InputIterator last,
@@ -254,6 +255,10 @@ public:
 
   //Assignement
   Triangulation_2 &operator=(const Triangulation_2 &tr);
+  Triangulation_2 &operator=(Triangulation_2 &&) = default;
+
+  // Destructor
+  ~Triangulation_2() = default;
 
   //Helping
   void copy_triangulation(const Triangulation_2 &tr);
@@ -628,7 +633,7 @@ std::ptrdiff_t insert(InputIterator first, InputIterator last,
          typename std::iterator_traits<InputIterator>::value_type,
          Point
          >
-         >::type* = NULL)
+         >::type* = nullptr)
 #else
   template < class InputIterator >
   std::ptrdiff_t
@@ -1016,7 +1021,7 @@ includes_edge(Vertex_handle va, Vertex_handle vb,
   Orientation orient;
   int indv;
   Edge_circulator ec = incident_edges(va), done(ec);
-  if (ec != 0) {
+  if (ec != nullptr) {
     do {
       //find the index of the other vertex of *ec
       indv = 3 - ((*ec).first)->index(va) - (*ec).second ;
@@ -2597,7 +2602,7 @@ march_locate_2D_LFC(Face_handle start,
   }else {
     lfc = Line_face_circulator(start->vertex(0), this, t);
   }
-  if(lfc==0 || lfc.collinear_outside()){
+  if(lfc==nullptr || lfc.collinear_outside()){
     // point t lies outside or on the convex hull
     // we walk on the convex hull to find it out
     Face_circulator fc = incident_faces(infinite_vertex());
diff --git a/Triangulation_2/include/CGAL/Triangulation_2/internal/Polyline_constraint_hierarchy_2.h b/Triangulation_2/include/CGAL/Triangulation_2/internal/Polyline_constraint_hierarchy_2.h
index 8f6fbc7fbed..c3c26ce2470 100644
--- a/Triangulation_2/include/CGAL/Triangulation_2/internal/Polyline_constraint_hierarchy_2.h
+++ b/Triangulation_2/include/CGAL/Triangulation_2/internal/Polyline_constraint_hierarchy_2.h
@@ -154,10 +154,6 @@ public:
   public:
     Context() : enclosing(nullptr) {}
 
-    Context(const Context& hc)
-      : enclosing(hc.enclosing), pos(hc.pos)
-    {}
-
     Vertex_it    vertices_begin()const { return enclosing->skip_begin();}
     Vertex_it    current()const {return pos;}
     Vertex_it    vertices_end()const {return enclosing->skip_end();}
@@ -187,9 +183,11 @@ public:
     , sc_to_c_map(Pair_compare(comp))
   { }
   Polyline_constraint_hierarchy_2(const Polyline_constraint_hierarchy_2& ch);
+  Polyline_constraint_hierarchy_2(Polyline_constraint_hierarchy_2&&) = default;
   ~Polyline_constraint_hierarchy_2(){ clear();}
   void clear();
   Polyline_constraint_hierarchy_2& operator=(const Polyline_constraint_hierarchy_2& ch);
+  Polyline_constraint_hierarchy_2& operator=(Polyline_constraint_hierarchy_2&& ch) = default;
 
   // Query
   bool is_subconstrained_edge(T va, T vb) const;
@@ -499,7 +497,7 @@ swap(Constraint_id first, Constraint_id second){
     // and replace the context of the constraint
     for(Context_iterator ctit=hcl->begin(); ctit != hcl->end(); ctit++) {
       if(ctit->enclosing == first.vl_ptr()){
-        ctit->enclosing = 0;
+        ctit->enclosing = nullptr;
         break;
       }
     }
@@ -530,7 +528,7 @@ swap(Constraint_id first, Constraint_id second){
 
     // and replace the context of the constraint
     for(Context_iterator ctit=hcl->begin(); ctit != hcl->end(); ctit++) {
-      if(ctit->enclosing == 0){
+      if(ctit->enclosing == nullptr){
         ctit->enclosing = second.vl_ptr();
         break;
       }
diff --git a/Triangulation_2/include/CGAL/Triangulation_hierarchy_2.h b/Triangulation_2/include/CGAL/Triangulation_hierarchy_2.h
index 264fab4c926..266c4964e03 100644
--- a/Triangulation_2/include/CGAL/Triangulation_hierarchy_2.h
+++ b/Triangulation_2/include/CGAL/Triangulation_hierarchy_2.h
@@ -36,6 +36,7 @@
 #include <iostream>
 #include <map>
 #include <vector>
+#include <array>
 
 namespace CGAL {
 
@@ -82,13 +83,25 @@ public:
 
  private:
   // here is the stack of triangulations which form the hierarchy
-  Tr_Base*   hierarchy[Triangulation_hierarchy_2__maxlevel];
+  std::array<Tr_Base*,Triangulation_hierarchy_2__maxlevel> hierarchy;
   boost::rand48  random;
 
 public:
   Triangulation_hierarchy_2(const Geom_traits& traits = Geom_traits());
   Triangulation_hierarchy_2(const Triangulation_hierarchy_2& tr);
 
+  Triangulation_hierarchy_2(Triangulation_hierarchy_2&& other)
+    noexcept( noexcept(Tr_Base(std::move(other))) )
+    : Tr_Base(std::move(other))
+    , random(std::move(other.random))
+  {
+    hierarchy[0] = this;
+    for(int i=1; i<Triangulation_hierarchy_2__maxlevel; ++i) {
+      hierarchy[i] = other.hierarchy[i];
+      other.hierarchy[i] = nullptr;
+    }
+  }
+
   template<class InputIterator>
   Triangulation_hierarchy_2(InputIterator first, InputIterator beyond,
                             const Geom_traits& traits = Geom_traits())
@@ -102,6 +115,19 @@ public:
   }
 
   Triangulation_hierarchy_2 &operator=(const  Triangulation_hierarchy_2& tr);
+
+  Triangulation_hierarchy_2 & operator=(Triangulation_hierarchy_2&& other)
+    noexcept( noexcept(Triangulation_hierarchy_2(std::move(other))) )
+  {
+    static_cast<Tr_Base&>(*this) = std::move(other);
+    hierarchy[0] = this;
+    for(int i=1; i<Triangulation_hierarchy_2__maxlevel; ++i) {
+      hierarchy[i] = other.hierarchy[i];
+      other.hierarchy[i] = nullptr;
+    }
+    return *this;
+  }
+
   ~Triangulation_hierarchy_2();
 
   //Helping
@@ -390,8 +416,8 @@ void
 Triangulation_hierarchy_2<Tr_>::
 clear()
 {
-        for(int i=0;i<Triangulation_hierarchy_2__maxlevel;++i)
-        hierarchy[i]->clear();
+  for(int i=0;i<Triangulation_hierarchy_2__maxlevel;++i)
+    if(hierarchy[i]) hierarchy[i]->clear();
 }
 
 
@@ -723,7 +749,7 @@ locate_in_all(const Point& p,
     level--;
   }
 
-  for (int i=level+1; i<Triangulation_hierarchy_2__maxlevel;++i) pos[i]=0;
+  for (int i=level+1; i<Triangulation_hierarchy_2__maxlevel;++i) pos[i]=nullptr;
   while(level > 0) {
     pos[level]=position=hierarchy[level]->locate(p, position);
     // locate at that level from "position"
diff --git a/Triangulation_2/include/CGAL/Triangulation_hierarchy_vertex_base_2.h b/Triangulation_2/include/CGAL/Triangulation_hierarchy_vertex_base_2.h
index 482d9897d33..e1e30c53706 100644
--- a/Triangulation_2/include/CGAL/Triangulation_hierarchy_vertex_base_2.h
+++ b/Triangulation_2/include/CGAL/Triangulation_hierarchy_vertex_base_2.h
@@ -41,13 +41,13 @@ public:
   };
 
   Triangulation_hierarchy_vertex_base_2()
-    : Base(), _up(0), _down(0)
+    : Base()
     {}
   Triangulation_hierarchy_vertex_base_2(const Point & p, Face_handle f)
-    : Base(p,f), _up(0), _down(0)
+    : Base(p,f)
     {}
   Triangulation_hierarchy_vertex_base_2(const Point & p)
-    : Base(p), _up(0), _down(0)
+    : Base(p)
     {}
 
   Vertex_handle up() {return _up;}
@@ -57,8 +57,8 @@ public:
 
 
  private:
-  Vertex_handle  _up;    // same vertex one level above
-  Vertex_handle  _down;  // same vertex one level below
+  Vertex_handle  _up   = nullptr;    // same vertex one level above
+  Vertex_handle  _down = nullptr;  // same vertex one level below
 };
 
 } //namespace CGAL
diff --git a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_const_Del_triangulation_2.h b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_const_Del_triangulation_2.h
index 2635832ee69..ccc193bad99 100644
--- a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_const_Del_triangulation_2.h
+++ b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_const_Del_triangulation_2.h
@@ -30,6 +30,16 @@ template <class Triangul>
 void
 _test_cls_const_Del_triangulation(const Triangul&)
 {
+  // The following assertion is commented, because, in CT_plus_2,
+  // one uses `std::set` and `std::map`, and their move-constructors
+  // may throw.
+  //
+  // static_assert(std::is_nothrow_move_constructible<Triangul>::value,
+  //               "move cstr is missing");
+
+  static_assert(std::is_nothrow_move_assignable<Triangul>::value,
+                "move assignment is missing");
+
   //typedef Triangulation                      Cls;
   typedef typename Triangul::Geom_traits          Gt;
 
diff --git a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_constrained_triangulation_2.h b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_constrained_triangulation_2.h
index fbe4b9ae725..fb62d70e19b 100644
--- a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_constrained_triangulation_2.h
+++ b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_constrained_triangulation_2.h
@@ -92,6 +92,16 @@ template <class Triang>
 void
 _test_cls_constrained_triangulation(const Triang &)
 {
+  // The following assertion is commented, because, in CT_plus_2,
+  // one uses `std::set` and `std::map`, and their move-constructors
+  // may throw.
+  //
+  // static_assert(std::is_nothrow_move_constructible<Triang>::value,
+  //               "move cstr is missing");
+
+  static_assert(std::is_nothrow_move_assignable<Triang>::value,
+                "move assignment is missing");
+
   // typedef Triangulation                       Cls;
   typedef typename Triang::Geom_traits          Gt;
 
diff --git a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_delaunay_triangulation_2.h b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_delaunay_triangulation_2.h
index d5088cb094d..b91d6eb534c 100644
--- a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_delaunay_triangulation_2.h
+++ b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_delaunay_triangulation_2.h
@@ -39,6 +39,11 @@ template <class Del>
 void
 _test_cls_delaunay_triangulation_2( const Del & )
 {
+  static_assert(std::is_nothrow_move_constructible<Del>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Del>::value,
+                "move assignment is missing");
+
   //typedef Del  Delaunay;
   typedef typename Del::Point                Point;
   typedef typename Del::Locate_type          Locate_type;
diff --git a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_triangulation_2.h b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_triangulation_2.h
index 096b6bc5d7a..348428439f7 100644
--- a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_triangulation_2.h
+++ b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_cls_triangulation_2.h
@@ -39,6 +39,10 @@ template <class Triangul>
 void
 _test_cls_triangulation_2( const Triangul & )
 {
+  static_assert(std::is_nothrow_move_constructible<Triangul>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Triangul>::value,
+                "move assignment is missing");
   //typedef Triangulation                      Cls;
 
   // We assume the traits class has been tested already
diff --git a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_traits.h b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_traits.h
index 45e4840383d..b472c7fc8d2 100644
--- a/Triangulation_2/test/Triangulation_2/include/CGAL/_test_traits.h
+++ b/Triangulation_2/test/Triangulation_2/include/CGAL/_test_traits.h
@@ -36,7 +36,6 @@ protected:
   double _x, _y;
 public:
   Triangulation_test_point() {}
-  Triangulation_test_point(const Point &p) : _x(p.test_x()), _y(p.test_y()) {}
   Triangulation_test_point(double x, double y) : _x(x), _y(y) {}
   Triangulation_test_point(double hx, double hy, double hw) :
     _x(hx/hw), _y(hy/hw)
@@ -47,7 +46,6 @@ public:
   bool   compare(const Point &p) const
     { return test_x()==p.test_x()  &&   test_y()==p.test_y(); }
   bool   uncompare(const Point &p) const { return !compare(p); }
-  Point  &operator=(const Point &p) { _x=p.test_x(); _y=p.test_y(); return *this; }
   void   test_set(TESTFT x, TESTFT y) { _x=x; _y=y; }
   bool operator==(const Point &p) const {return this->compare(p);}
 };
@@ -436,11 +434,6 @@ public:
   typedef Triangulation_test_Construct_ray_2       Construct_ray_2;
 
 
-  _Triangulation_test_traits() {}
-  _Triangulation_test_traits(const _Triangulation_test_traits &) {}
-  _Triangulation_test_traits &operator=
-        (const _Triangulation_test_traits &) { return *this; }
-
   Less_x_2
   less_x_2_object() const
     { return Less_x_2();}
diff --git a/Triangulation_2/test/Triangulation_2/issue_4405.cpp b/Triangulation_2/test/Triangulation_2/issue_4405.cpp
index 89199d56141..770cd6c761c 100644
--- a/Triangulation_2/test/Triangulation_2/issue_4405.cpp
+++ b/Triangulation_2/test/Triangulation_2/issue_4405.cpp
@@ -9,13 +9,43 @@ typedef CGAL::Epick Kernel;
 typedef Kernel::FT FieldNumberType;
 typedef Kernel::Point_2 Point2;
 typedef Kernel::Point_3 Point3;
+
+template <typename Vb>
+class My_vertex_base : public Vb {
+  std::size_t time_stamp_;
+public:
+  My_vertex_base() : Vb(), time_stamp_(-1) {
+  }
+
+  My_vertex_base(const My_vertex_base& other) :
+    Vb(other),
+    time_stamp_(other.time_stamp_)
+  {}
+
+  typedef CGAL::Tag_true Has_timestamp;
+
+  std::size_t time_stamp() const {
+    return time_stamp_;
+  }
+  void set_time_stamp(const std::size_t& ts) {
+    time_stamp_ = ts;
+  }
+
+  template < class TDS >
+  struct Rebind_TDS {
+    typedef typename Vb::template Rebind_TDS<TDS>::Other Vb2;
+    typedef My_vertex_base<Vb2> Other;
+  };
+};
+
 struct FaceInfo2
 {
   unsigned long long m_id;
 };
 typedef CGAL::Projection_traits_xy_3<Kernel> TriangulationTraits;
 typedef CGAL::Triangulation_vertex_base_with_id_2<TriangulationTraits> VertexBaseWithId;
-typedef CGAL::Triangulation_vertex_base_2<TriangulationTraits, VertexBaseWithId> VertexBase;
+typedef My_vertex_base<VertexBaseWithId> Vb2;
+typedef CGAL::Triangulation_vertex_base_2<TriangulationTraits, Vb2> VertexBase;
 typedef CGAL::Triangulation_face_base_with_info_2<FaceInfo2, Kernel> FaceBaseWithInfo;
 typedef CGAL::Constrained_triangulation_face_base_2<TriangulationTraits, FaceBaseWithInfo> FaceBase;
 typedef CGAL::Triangulation_data_structure_2<VertexBase, FaceBase> TriangulationData;
diff --git a/Triangulation_2/test/Triangulation_2/test_cdt_degenerate_case.cpp b/Triangulation_2/test/Triangulation_2/test_cdt_degenerate_case.cpp
index 5dc1d1c7afa..b4de0e1e0f7 100644
--- a/Triangulation_2/test/Triangulation_2/test_cdt_degenerate_case.cpp
+++ b/Triangulation_2/test/Triangulation_2/test_cdt_degenerate_case.cpp
@@ -1,3 +1,4 @@
+#define CGAL_CDT_2_DEBUG_INTERSECTIONS 1
 #include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
 #include <CGAL/Constrained_Delaunay_triangulation_2.h>
 #include <CGAL/Constrained_triangulation_plus_2.h>
@@ -5,7 +6,41 @@
 
 typedef CGAL::Exact_predicates_inexact_constructions_kernel EPIC;
 typedef EPIC::Point_2 Point_2;
-typedef CGAL::Triangulation_vertex_base_2<EPIC> Vb;
+
+template <typename Vb>
+class My_vertex_base : public Vb {
+  std::size_t time_stamp_;
+public:
+  My_vertex_base() : Vb(), time_stamp_(-1) {
+  }
+
+  My_vertex_base(const My_vertex_base& other) :
+    Vb(other),
+    time_stamp_(other.time_stamp_)
+  {}
+
+  typedef CGAL::Tag_true Has_timestamp;
+
+  std::size_t time_stamp() const {
+    return time_stamp_;
+  }
+  void set_time_stamp(const std::size_t& ts) {
+    time_stamp_ = ts;
+  }
+
+  template < class TDS >
+  struct Rebind_TDS {
+    typedef typename Vb::template Rebind_TDS<TDS>::Other Vb2;
+    typedef My_vertex_base<Vb2> Other;
+  };
+};
+
+#ifdef CGAL_CDT_2_DEBUG_INTERSECTIONS
+typedef My_vertex_base<CGAL::Triangulation_vertex_base_2<EPIC> > Vb;
+#else
+typedef CGAL::Triangulation_vertex_base_2<K> Vb;
+#endif
+
 typedef CGAL::Constrained_triangulation_face_base_2<EPIC> Fb;
 typedef CGAL::Triangulation_data_structure_2<Vb, Fb> TDS;
 typedef CGAL::Exact_predicates_tag Itag;
@@ -14,6 +49,7 @@ typedef CGAL::Constrained_triangulation_plus_2<CDT> CDTp2;
 
 template <class CDT>
 void test() {
+  std::cerr.precision(17);
   CDT cdt;
   cdt.insert_constraint(Point_2(  48.0923419883269,   299.7232779774145  ),
                         Point_2(  66.05373710316852,  434.231770798343   ));
diff --git a/Triangulation_3/benchmark/Triangulation_3/CMakeLists.txt b/Triangulation_3/benchmark/Triangulation_3/CMakeLists.txt
index c6892abd08e..4d0c7c1c778 100644
--- a/Triangulation_3/benchmark/Triangulation_3/CMakeLists.txt
+++ b/Triangulation_3/benchmark/Triangulation_3/CMakeLists.txt
@@ -49,14 +49,12 @@ find_package(benchmark)
 
 if(TARGET benchmark::benchmark)
   find_package(TBB REQUIRED)
-  include( CGAL_target_use_TBB )
+  include(CGAL_TBB_support)
 
   create_single_source_cgal_program( "DT3_benchmark_with_TBB.cpp" )
-  CGAL_target_use_TBB(DT3_benchmark_with_TBB)
-  target_link_libraries(DT3_benchmark_with_TBB PRIVATE benchmark::benchmark)
+  target_link_libraries(DT3_benchmark_with_TBB PRIVATE benchmark::benchmark CGAL::TBB_support)
 
   add_executable(DT3_benchmark_with_TBB_CCC_approximate_size DT3_benchmark_with_TBB.cpp)
-  CGAL_target_use_TBB(DT3_benchmark_with_TBB_CCC_approximate_size)
   target_compile_definitions(DT3_benchmark_with_TBB_CCC_approximate_size PRIVATE CGAL_CONCURRENT_COMPACT_CONTAINER_APPROXIMATE_SIZE)
-  target_link_libraries(DT3_benchmark_with_TBB_CCC_approximate_size PRIVATE CGAL::CGAL benchmark::benchmark)
+  target_link_libraries(DT3_benchmark_with_TBB_CCC_approximate_size PRIVATE CGAL::CGAL benchmark::benchmark CGAL::TBB_support)
 endif()
diff --git a/Triangulation_3/demo/Triangulation_3/CMakeLists.txt b/Triangulation_3/demo/Triangulation_3/CMakeLists.txt
index 99856041fc3..0f3412b545f 100644
--- a/Triangulation_3/demo/Triangulation_3/CMakeLists.txt
+++ b/Triangulation_3/demo/Triangulation_3/CMakeLists.txt
@@ -37,12 +37,14 @@ option(CGAL_ACTIVATE_CONCURRENT_TRIANGULATION_3
 if( CGAL_ACTIVATE_CONCURRENT_TRIANGULATION_3 )
   add_definitions( -DCGAL_CONCURRENT_TRIANGULATION_3 )
   find_package( TBB REQUIRED )
+  include(CGAL_TBB_support)
 else( CGAL_ACTIVATE_CONCURRENT_TRIANGULATION_3 )
   option( LINK_WITH_TBB
     "Link with TBB anyway so we can use TBB timers for profiling"
     ON)
   if( LINK_WITH_TBB )
     find_package( TBB )
+    include(CGAL_TBB_support)
   endif( LINK_WITH_TBB )
 endif()
 
@@ -67,8 +69,8 @@ if ( CGAL_FOUND AND CGAL_Qt5_FOUND AND Qt5_FOUND )
 
   target_link_libraries( T3_demo PRIVATE CGAL::CGAL CGAL::CGAL_Qt5)
   target_link_libraries( T3_demo PRIVATE Qt5::OpenGL Qt5::Xml)
-  if(TBB_FOUND)
-    CGAL_target_use_TBB(T3_demo)
+  if(TARGET CGAL::TBB_support)
+    target_link_libraries(T3_demo PUBLIC CGAL::TBB_support)
   endif()
 
   include(${CGAL_MODULES_DIR}/CGAL_add_test.cmake)
diff --git a/Triangulation_3/examples/Triangulation_3/CMakeLists.txt b/Triangulation_3/examples/Triangulation_3/CMakeLists.txt
index d6bd426e464..a44531dec74 100644
--- a/Triangulation_3/examples/Triangulation_3/CMakeLists.txt
+++ b/Triangulation_3/examples/Triangulation_3/CMakeLists.txt
@@ -39,16 +39,15 @@ if ( CGAL_FOUND )
   endif()
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
 
-  if( TBB_FOUND )
-    include( CGAL_target_use_TBB )
-
+  if( TARGET CGAL::TBB_support )
     create_single_source_cgal_program( "parallel_insertion_and_removal_in_regular_3.cpp" )
     create_single_source_cgal_program( "parallel_insertion_in_delaunay_3.cpp" )
     create_single_source_cgal_program( "sequential_parallel.cpp" )
-    CGAL_target_use_TBB( parallel_insertion_and_removal_in_regular_3 )
-    CGAL_target_use_TBB( parallel_insertion_in_delaunay_3 )
-    CGAL_target_use_TBB( sequential_parallel )
+    target_link_libraries( parallel_insertion_and_removal_in_regular_3 PUBLIC CGAL::TBB_support)
+    target_link_libraries( parallel_insertion_in_delaunay_3 PUBLIC CGAL::TBB_support )
+    target_link_libraries( sequential_parallel  PUBLIC CGAL::TBB_support)
   else()
     message(STATUS "NOTICE: a few examples require TBB and will not be compiled.")
   endif()
@@ -58,4 +57,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Triangulation_3/include/CGAL/Delaunay_triangulation_3.h b/Triangulation_3/include/CGAL/Delaunay_triangulation_3.h
index e5dbec51447..108188ff824 100644
--- a/Triangulation_3/include/CGAL/Delaunay_triangulation_3.h
+++ b/Triangulation_3/include/CGAL/Delaunay_triangulation_3.h
@@ -888,11 +888,6 @@ protected:
     : m_dt(dt), m_points(points), m_tls_hint(tls_hint)
     {}
 
-    // Constructor
-    Insert_point(const Insert_point& ip)
-    : m_dt(ip.m_dt), m_points(ip.m_points), m_tls_hint(ip.m_tls_hint)
-    {}
-
     // operator()
     void operator()(const tbb::blocked_range<size_t>& r) const
     {
@@ -968,12 +963,6 @@ protected:
       m_tls_hint(tls_hint)
     {}
 
-    // Constructor
-    Insert_point_with_info(const Insert_point_with_info& ip)
-      : m_dt(ip.m_dt), m_points(ip.m_points), m_infos(ip.m_infos),
-      m_indices(ip.m_indices), m_tls_hint(ip.m_tls_hint)
-    {}
-
     // operator()
     void operator()(const tbb::blocked_range<size_t>& r) const
     {
@@ -1047,12 +1036,6 @@ protected:
       m_vertices_to_remove_sequentially(vertices_to_remove_sequentially)
     {}
 
-    // Constructor
-    Remove_point(const Remove_point& rp)
-    : m_dt(rp.m_dt), m_vertices(rp.m_vertices),
-      m_vertices_to_remove_sequentially(rp.m_vertices_to_remove_sequentially)
-    {}
-
     // operator()
     void operator()(const tbb::blocked_range<size_t>& r) const
     {
diff --git a/Triangulation_3/include/CGAL/Delaunay_triangulation_cell_base_with_circumcenter_3.h b/Triangulation_3/include/CGAL/Delaunay_triangulation_cell_base_with_circumcenter_3.h
index f8ac6a7a232..14fc74d8490 100644
--- a/Triangulation_3/include/CGAL/Delaunay_triangulation_cell_base_with_circumcenter_3.h
+++ b/Triangulation_3/include/CGAL/Delaunay_triangulation_cell_base_with_circumcenter_3.h
@@ -63,6 +63,12 @@ public:
     : Cb(c), circumcenter_(c.circumcenter_ != nullptr ? new Point(*(c.circumcenter_)) : nullptr)
   {}
 
+  Delaunay_triangulation_cell_base_with_circumcenter_3
+        (Delaunay_triangulation_cell_base_with_circumcenter_3 &&c)
+    : Cb(std::move(c)), circumcenter_(std::exchange(c.circumcenter_, nullptr))
+  {
+  }
+
   Delaunay_triangulation_cell_base_with_circumcenter_3&
   operator=(const Delaunay_triangulation_cell_base_with_circumcenter_3 &c)
   {
@@ -71,6 +77,14 @@ public:
       return *this;
   }
 
+  Delaunay_triangulation_cell_base_with_circumcenter_3&
+  operator=(Delaunay_triangulation_cell_base_with_circumcenter_3 &&c)
+  {
+      Cb::operator=(std::move(c));
+      circumcenter_ = std::exchange(c.circumcenter_, nullptr);
+      return *this;
+  }
+
   Delaunay_triangulation_cell_base_with_circumcenter_3(
                             Vertex_handle v0, Vertex_handle v1,
                             Vertex_handle v2, Vertex_handle v3)
diff --git a/Triangulation_3/include/CGAL/Regular_triangulation_3.h b/Triangulation_3/include/CGAL/Regular_triangulation_3.h
index b1a55c9eabe..2e490a7c861 100644
--- a/Triangulation_3/include/CGAL/Regular_triangulation_3.h
+++ b/Triangulation_3/include/CGAL/Regular_triangulation_3.h
@@ -199,21 +199,38 @@ public:
     CGAL_triangulation_postcondition(is_valid());
   }
 
+  Regular_triangulation_3(Regular_triangulation_3&& rt)
+    noexcept(noexcept(Tr_Base(std::move(rt))))
+    : Tr_Base(std::move(rt)), hidden_point_visitor(this)
+  {
+    CGAL_triangulation_postcondition(is_valid());
+  }
+
+  ~Regular_triangulation_3() = default;
+
   void swap(Regular_triangulation_3& tr)
   {
-    // The 'vertices' and 'hidden_points' members of 'hidden_point_visitor' should be empty
-    // as they are only filled (and cleared) during the insertion of a point.
-    // Hidden points are not stored there, but rather in cells. Thus, the only thing that must be set
-    // is the triangulation pointer.
-    Hidden_point_visitor<Concurrency_tag> new_hpv(this);
-    std::swap(hidden_point_visitor, new_hpv);
-
+    // The 'vertices' and 'hidden_points' members of
+    // 'hidden_point_visitor' should be empty as they are only filled
+    // (and cleared) during the insertion of a point.  Hidden points
+    // are not stored there, but rather in cells. Thus, the only thing
+    // that must be set is the triangulation pointer, and it is
+    // already correctly set. There is nothing to do about
+    // 'hidden_point_visitor'.
     Tr_Base::swap(tr);
   }
 
-  Regular_triangulation_3& operator=(Regular_triangulation_3 tr)
+  Regular_triangulation_3& operator=(const Regular_triangulation_3& tr)
   {
-    swap(tr);
+    Regular_triangulation_3 copy(tr);
+    copy.swap(*this);
+    return *this;
+  }
+
+  Regular_triangulation_3& operator=(Regular_triangulation_3&& tr)
+    noexcept(noexcept(Regular_triangulation_3(std::move(tr))))
+  {
+    Tr_Base::operator=(std::move(tr));
     return *this;
   }
 
@@ -1393,11 +1410,6 @@ protected:
       : m_rt(rt), m_points(points), m_tls_hint(tls_hint)
     {}
 
-    // Constructor
-    Insert_point(const Insert_point& ip)
-      : m_rt(ip.m_rt), m_points(ip.m_points), m_tls_hint(ip.m_tls_hint)
-    {}
-
     // operator()
     void operator()(const tbb::blocked_range<size_t>& r) const
     {
@@ -1504,12 +1516,6 @@ protected:
         m_tls_hint(tls_hint)
     {}
 
-    // Constructor
-    Insert_point_with_info(const Insert_point_with_info &ip)
-      : m_rt(ip.m_rt), m_points(ip.m_points), m_infos(ip.m_infos),
-        m_indices(ip.m_indices), m_tls_hint(ip.m_tls_hint)
-    {}
-
     // operator()
     void operator()(const tbb::blocked_range<size_t>& r) const
     {
@@ -1621,12 +1627,6 @@ protected:
         m_vertices_to_remove_sequentially(vertices_to_remove_sequentially)
     {}
 
-    // Constructor
-    Remove_point(const Remove_point& rp)
-      : m_rt(rp.m_rt), m_vertices(rp.m_vertices),
-        m_vertices_to_remove_sequentially(rp.m_vertices_to_remove_sequentially)
-    {}
-
     // operator()
     void operator()(const tbb::blocked_range<size_t>& r) const
     {
diff --git a/Triangulation_3/include/CGAL/Triangulation_3.h b/Triangulation_3/include/CGAL/Triangulation_3.h
index ed728066e72..e120cac0ad0 100644
--- a/Triangulation_3/include/CGAL/Triangulation_3.h
+++ b/Triangulation_3/include/CGAL/Triangulation_3.h
@@ -179,7 +179,7 @@ public:
 
   void *get_lock_data_structure() const
   {
-    return 0;
+    return nullptr;
   }
 
   void set_lock_data_structure(void *) const {}
@@ -245,7 +245,7 @@ protected:
 public:
   bool is_parallel() const
   {
-    return m_lock_ds != 0;
+    return m_lock_ds != nullptr;
   }
 
   // LOCKS
@@ -731,6 +731,9 @@ public:
     CGAL_triangulation_expensive_postcondition(*this == tr);
   }
 
+  Triangulation_3(Triangulation_3&& tr) = default;
+  ~Triangulation_3() = default;
+
   template < typename InputIterator >
   Triangulation_3(InputIterator first, InputIterator last,
                   const GT& gt = GT(), Lock_data_structure *lock_ds = nullptr)
@@ -757,21 +760,21 @@ public:
     init_tds();
   }
 
-  Triangulation_3& operator=(Triangulation_3 tr)
+  Triangulation_3& operator=(const Triangulation_3& tr)
   {
-    // Because the parameter tr is passed by value, the triangulation passed
-    // as argument has been copied.
-    // The following 'swap' consumes the *copy* and the original triangulation
-    // is left untouched.
-    swap(tr);
+    Triangulation_3 copy(tr);
+    swap(copy);
     return *this;
   }
 
+  Triangulation_3& operator=(Triangulation_3&& tr) = default;
+
   // HELPING FUNCTIONS
-  void swap(Triangulation_3& tr)
+  void swap(Triangulation_3& tr) noexcept
   {
-    std::swap(tr._gt, _gt);
-    std::swap(tr.infinite, infinite);
+    using std::swap;
+    swap(tr._gt, _gt);
+    swap(tr.infinite, infinite);
     _tds.swap(tr._tds);
     Base::swap(tr);
   }
@@ -1139,7 +1142,7 @@ public:
                               typename std::iterator_traits<InputIterator>::value_type,
                               Point
                           >
-                        >::type* = NULL)
+                        >::type* = nullptr)
 #else
   template < class InputIterator >
   std::ptrdiff_t insert(InputIterator first, InputIterator last)
diff --git a/Triangulation_3/include/CGAL/Triangulation_hierarchy_3.h b/Triangulation_3/include/CGAL/Triangulation_hierarchy_3.h
index c0326a14b2a..0831c09c656 100644
--- a/Triangulation_3/include/CGAL/Triangulation_hierarchy_3.h
+++ b/Triangulation_3/include/CGAL/Triangulation_hierarchy_3.h
@@ -50,6 +50,8 @@
 #include <boost/mpl/identity.hpp>
 #include <boost/mpl/if.hpp>
 
+#include <array>
+
 #endif //CGAL_TRIANGULATION_3_DONT_INSERT_RANGE_OF_POINTS_WITH_INFO
 
 namespace CGAL {
@@ -91,7 +93,7 @@ public:
 private:
 
   // here is the stack of triangulations which form the hierarchy
-  Tr_Base*       hierarchy[maxlevel];
+  std::array<Tr_Base*,maxlevel> hierarchy;
   boost::rand48  random;
 
   void set_up_down(Vertex_handle up, Vertex_handle down)
@@ -106,6 +108,18 @@ public:
 
   Triangulation_hierarchy_3(const Triangulation_hierarchy_3& tr);
 
+  Triangulation_hierarchy_3(Triangulation_hierarchy_3&& other)
+    noexcept( noexcept(Tr_Base(std::move(other))) )
+    : Tr_Base(std::move(other))
+    , random(std::move(other.random))
+  {
+    hierarchy[0] = this;
+    for(int i=1; i<maxlevel; ++i) {
+      hierarchy[i] = other.hierarchy[i];
+      other.hierarchy[i] = nullptr;
+    }
+  }
+
   template < typename InputIterator >
   Triangulation_hierarchy_3(InputIterator first, InputIterator last,
                             const Geom_traits& traits = Geom_traits())
@@ -124,9 +138,32 @@ public:
     return *this;
   }
 
-  ~Triangulation_hierarchy_3();
+  Triangulation_hierarchy_3 & operator=(Triangulation_hierarchy_3&& other)
+    noexcept( noexcept(Triangulation_hierarchy_3(std::move(other))) )
+  {
+    static_cast<Tr_Base&>(*this) = std::move(other);
+    hierarchy[0] = this;
+    for(int i=1; i<maxlevel; ++i) {
+      hierarchy[i] = other.hierarchy[i];
+      other.hierarchy[i] = nullptr;
+    }
+    return *this;
+  }
 
-  void swap(Triangulation_hierarchy_3 &tr);
+  ~Triangulation_hierarchy_3()
+  {
+    clear();
+    for(int i=1; i<maxlevel; ++i) {
+      delete hierarchy[i];
+    }
+  };
+
+  void swap(Triangulation_hierarchy_3 &tr)
+  {
+    Tr_Base::swap(tr);
+    for(int i=1; i<maxlevel; ++i)
+      std::swap(hierarchy[i], tr.hierarchy[i]);
+  };
 
   void clear();
 
@@ -461,26 +498,6 @@ Triangulation_hierarchy_3(const Triangulation_hierarchy_3<Tr> &tr)
   }
 }
 
-template <class Tr>
-void
-Triangulation_hierarchy_3<Tr>::
-swap(Triangulation_hierarchy_3<Tr> &tr)
-{
-  Tr_Base::swap(tr);
-  for(int i=1; i<maxlevel; ++i)
-      std::swap(hierarchy[i], tr.hierarchy[i]);
-}
-
-template <class Tr>
-Triangulation_hierarchy_3<Tr>::
-~Triangulation_hierarchy_3()
-{
-  clear();
-  for(int i=1; i<maxlevel; ++i) {
-    delete hierarchy[i];
-  }
-}
-
 template <class Tr>
 void
 Triangulation_hierarchy_3<Tr>::
diff --git a/Triangulation_3/test/Triangulation_3/CMakeLists.txt b/Triangulation_3/test/Triangulation_3/CMakeLists.txt
index a2d10b47143..4dfcc8c4bb5 100644
--- a/Triangulation_3/test/Triangulation_3/CMakeLists.txt
+++ b/Triangulation_3/test/Triangulation_3/CMakeLists.txt
@@ -12,6 +12,7 @@ find_package(CGAL QUIET)
 if ( CGAL_FOUND )
 
   find_package( TBB QUIET )
+  include(CGAL_TBB_support)
 
   include_directories (BEFORE "include")
 
@@ -30,12 +31,12 @@ if ( CGAL_FOUND )
   create_single_source_cgal_program( "test_triangulation_3.cpp" )
   create_single_source_cgal_program( "test_io_triangulation_3.cpp" )
 
-  if(TBB_FOUND)
+  if(TARGET CGAL::TBB_support)
     foreach(target
         test_delaunay_3
         test_regular_3
         test_regular_insert_range_with_info)
-      CGAL_target_use_TBB(${target})
+      target_link_libraries(${target} PUBLIC CGAL::TBB_support)
     endforeach()
   endif()
 
@@ -54,4 +55,3 @@ else()
     message(STATUS "This program requires the CGAL library, and will not be compiled.")
 
 endif()
-
diff --git a/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_delaunay_3.h b/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_delaunay_3.h
index 8eef60ae345..f7d4579828c 100644
--- a/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_delaunay_3.h
+++ b/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_delaunay_3.h
@@ -19,6 +19,7 @@
 #include <fstream>
 #include <list>
 #include <vector>
+#include <type_traits>
 
 #include <boost/mpl/identity.hpp>
 #include <boost/mpl/if.hpp>
@@ -170,6 +171,11 @@ _test_cls_delaunay_3(const Triangulation &)
 {
   typedef Triangulation                      Cls;
 
+  static_assert(std::is_nothrow_move_constructible<Cls>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Cls>::value,
+                "move assignment is missing");
+
   typedef typename Test_location_policy<Cls>::Location_policy Location_policy;
 
   // We assume the traits class has been tested already
diff --git a/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_regular_3.h b/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_regular_3.h
index c9630054c56..fba2db023fd 100644
--- a/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_regular_3.h
+++ b/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_regular_3.h
@@ -15,12 +15,19 @@
 #include <iostream>
 #include <fstream>
 #include <list>
+#include <type_traits>
 #include <CGAL/use.h>
 template <class Triangulation>
 void
 _test_cls_regular_3(const Triangulation &)
 {
   typedef Triangulation                       Cls;
+
+  static_assert(std::is_nothrow_move_constructible<Cls>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Cls>::value,
+                "move assignment is missing");
+
   typedef typename Triangulation::Geom_traits Gt;
   CGAL_USE_TYPE(Gt);
 
diff --git a/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_triangulation_3.h b/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_triangulation_3.h
index 015906a4e01..ded18a9175f 100644
--- a/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_triangulation_3.h
+++ b/Triangulation_3/test/Triangulation_3/include/CGAL/_test_cls_triangulation_3.h
@@ -15,6 +15,7 @@
 #include <fstream>
 #include <list>
 #include <vector>
+#include <type_traits>
 
 #include "_test_cls_iterator.h"
 #include "_test_cls_circulator.h"
@@ -79,6 +80,11 @@ _test_cls_triangulation_3(const Triangulation &)
 {
   typedef Triangulation                      Cls;
 
+  static_assert(std::is_nothrow_move_constructible<Cls>::value,
+                "move cstr is missing");
+  static_assert(std::is_nothrow_move_assignable<Cls>::value,
+                "move assignment is missing");
+
   // We assume the traits class has been tested already
   // actually, any traits is good if it has been tested
 
diff --git a/Union_find/include/CGAL/Union_find.h b/Union_find/include/CGAL/Union_find.h
index a76cf515856..16dc14bdb74 100644
--- a/Union_find/include/CGAL/Union_find.h
+++ b/Union_find/include/CGAL/Union_find.h
@@ -114,8 +114,7 @@ public:
 #ifdef _MSC_VER
     typedef CGAL_ALLOCATOR(Union_find_struct)                allocator;
 #else
-    typedef typename A::template rebind<Union_find_struct>   Rebind;
-    typedef typename Rebind::other                           allocator;
+    typedef typename std::allocator_traits<A>::template rebind_alloc<Union_find_struct> allocator;
 #endif
 
 private: