diff --git a/gfx/layers/apz/src/OverscrollHandoffState.h b/gfx/layers/apz/src/OverscrollHandoffState.h
index 95ddc027ba0..2c3a81154f1 100644
--- a/gfx/layers/apz/src/OverscrollHandoffState.h
+++ b/gfx/layers/apz/src/OverscrollHandoffState.h
@@ -10,6 +10,7 @@
 #include <vector>
 #include "nsAutoPtr.h"
 #include "nsISupportsImpl.h"  // for NS_INLINE_DECL_REFCOUNTING
+#include "Units.h"            // for ScreenPoint
 
 namespace mozilla {
 namespace layers {