diff --git a/Kernel_23/include/CGAL/Projection_traits_xy_3.h b/Kernel_23/include/CGAL/Projection_traits_xy_3.h
index e1e779f7955..301a8348df3 100644
--- a/Kernel_23/include/CGAL/Projection_traits_xy_3.h
+++ b/Kernel_23/include/CGAL/Projection_traits_xy_3.h
@@ -14,6 +14,7 @@
 #define CGAL_PROJECTION_TRAITS_XY_3_H
 
 #include <CGAL/Kernel_23/internal/Projection_traits_3.h>
+#include <CGAL/Triangulation_structural_filtering_traits.h>
 
 namespace CGAL {
 
@@ -22,6 +23,11 @@ class Projection_traits_xy_3
   : public internal::Projection_traits_3<R,2>
 {};
 
+template < class R >
+struct Triangulation_structural_filtering_traits<Projection_traits_xy_3<R> > {
+  typedef typename Triangulation_structural_filtering_traits<R>::Use_structural_filtering_tag  Use_structural_filtering_tag;
+};
+
 } //namespace CGAL
 
 #endif // CGAL_PROJECTION_TRAITS_XY_3_H