diff --git a/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoPolyhedron.h b/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoPolyhedron.h
index 86ab8fd517147b75c3ff5eccb6bf799ef67f75c3..06bf1f3d5e3adc44aa58d19cd488cdab9c39f968 100644
--- a/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoPolyhedron.h
+++ b/GeoModelCore/GeoModelKernel/GeoModelKernel/GeoPolyhedron.h
@@ -167,6 +167,7 @@
 
 class GeoPolyhedron
 {
+  friend class Geo_BooleanProcessor;
   friend std::ostream & operator<< (std::ostream &, const GeoPolyhedron & ph);
 
 private: