diff --git a/Interpolation/include/CGAL/regular_neighbor_coordinates_2.h b/Interpolation/include/CGAL/regular_neighbor_coordinates_2.h
index 7fbb978bf8c..ce5c62c0b76 100644
--- a/Interpolation/include/CGAL/regular_neighbor_coordinates_2.h
+++ b/Interpolation/include/CGAL/regular_neighbor_coordinates_2.h
@@ -20,6 +20,7 @@
 #include <CGAL/iterator.h>
 #include <CGAL/utility.h>
 #include <CGAL/function_objects.h>
+#include <CGAL/Polygon_2_algorithms.h>
 
 #include <boost/utility/enable_if.hpp>
 #include <boost/type_traits/is_convertible.hpp>