diff --git a/when/when.d.ts b/when/when.d.ts
index 859618852..2af3fba9d 100644
--- a/when/when.d.ts
+++ b/when/when.d.ts
@@ -78,3 +78,5 @@ declare module When {
         reason?: any;
     }
 }
+
+export = When;