diff --git a/Interpolation/include/CGAL/natural_neighbor_coordinates_2.h b/Interpolation/include/CGAL/natural_neighbor_coordinates_2.h
index c20d9e3ebc2..ff6a574d67b 100644
--- a/Interpolation/include/CGAL/natural_neighbor_coordinates_2.h
+++ b/Interpolation/include/CGAL/natural_neighbor_coordinates_2.h
@@ -24,6 +24,7 @@
 #include <CGAL/Iterator_project.h>
 #include <CGAL/Polygon_2.h>
 #include <CGAL/number_utils_classes.h>
+#include <CGAL/utility.h>
 
 CGAL_BEGIN_NAMESPACE