diff --git a/source/include/marlin/EventSelector.h b/source/include/marlin/EventSelector.h
index 1d1fac5c..e3e287c7 100644
--- a/source/include/marlin/EventSelector.h
+++ b/source/include/marlin/EventSelector.h
@@ -23,6 +23,7 @@ using namespace marlin ;
  * @author F. Gaede, DESY
  * @version $Id:$ 
  */
+namespace marlin {
 
 class EventSelector : public Processor, public marlin::EventModifier {
   
@@ -73,6 +74,8 @@ class EventSelector : public Processor, public marlin::EventModifier {
   int _nEvt=-1;
 } ;
 
+} // namespace marlin
+
 #endif