diff --git a/include/wx/splitter.h b/include/wx/splitter.h
index 4a74ca9c1a..1d55c78821 100644
--- a/include/wx/splitter.h
+++ b/include/wx/splitter.h
@@ -1,6 +1,8 @@
 #ifndef _WX_SPLITTER_H_BASE_
 #define _WX_SPLITTER_H_BASE_
 
+#include "wx/event.h"
+
 BEGIN_DECLARE_EVENT_TYPES()
     DECLARE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGED, 850)
     DECLARE_EVENT_TYPE(wxEVT_COMMAND_SPLITTER_SASH_POS_CHANGING, 851)