diff --git a/public/vgui_controls/Panel.h b/public/vgui_controls/Panel.h
index e1ce9cfa..cbb444bf 100644
--- a/public/vgui_controls/Panel.h
+++ b/public/vgui_controls/Panel.h
@@ -12,6 +12,7 @@
 #pragma once
 #endif
 
+#include "tier1/KeyValues.h"
 #include "tier1/utlflags.h"
 #include "vgui/VGUI.h"
 #include "vgui/Dar.h"