diff --git a/Packages/Partition_2/include/CGAL/Triangulation_indirect_traits_2.h b/Packages/Partition_2/include/CGAL/Triangulation_indirect_traits_2.h
index a80d44d3b5c..69f201ec423 100644
--- a/Packages/Partition_2/include/CGAL/Triangulation_indirect_traits_2.h
+++ b/Packages/Partition_2/include/CGAL/Triangulation_indirect_traits_2.h
@@ -29,6 +29,8 @@
 #ifndef CGAL_TRIANGULATION_INDIRECT_TRAITS_2_H
 #define CGAL_TRIANGULATION_INDIRECT_TRAITS_2_H
 
+#include <CGAL/Kernel/function_objects.h>
+
 namespace CGAL {
 
 template <class Circulator>