diff --git a/include/wx/os2/bmpbuttn.h b/include/wx/os2/bmpbuttn.h
index cad7e1cc4a..2185eea285 100644
--- a/include/wx/os2/bmpbuttn.h
+++ b/include/wx/os2/bmpbuttn.h
@@ -13,6 +13,7 @@
 #define _WX_BMPBUTTN_H_
 
 #include "wx/button.h"
+#include "wx/dcclient.h"
 
 WXDLLEXPORT_DATA(extern const char*) wxButtonNameStr;