diff --git a/include/gdiplusflat.h b/include/gdiplusflat.h
index 4aed5d3c45c..7c4fa70d141 100644
--- a/include/gdiplusflat.h
+++ b/include/gdiplusflat.h
@@ -528,6 +528,10 @@ GpStatus WINGDIPAPI GdipGetMetafileHeaderFromMetafile(GpMetafile*,MetafileHeader
 GpStatus WINGDIPAPI GdipGetMetafileHeaderFromStream(IStream*,MetafileHeader*);
 GpStatus WINGDIPAPI GdipGetMetafileHeaderFromWmf(HMETAFILE,GDIPCONST WmfPlaceableFileHeader*,MetafileHeader*);
 
+/* Notification */
+GpStatus WINAPI GdiplusNotificationHook(ULONG_PTR*);
+void WINAPI GdiplusNotificationUnhook(ULONG_PTR);
+
 /* PathGradientBrush */
 GpStatus WINGDIPAPI GdipCreatePathGradient(GDIPCONST GpPointF*,INT,GpWrapMode,GpPathGradient**);
 GpStatus WINGDIPAPI GdipCreatePathGradientI(GDIPCONST GpPoint*,INT,GpWrapMode,GpPathGradient**);