diff --git a/openbox/event.h b/openbox/event.h
index 05f9e0c2..e2b57ffe 100644
--- a/openbox/event.h
+++ b/openbox/event.h
@@ -20,6 +20,7 @@
 #define __events_h
 
 #include <X11/Xlib.h>
+#include <glib.h>
 
 /*! Time at which the last event with a timestamp occured. */
 extern Time event_lasttime;