diff --git a/xpinstall/public/nsIXPInstallProgress.idl b/xpinstall/public/nsIXPInstallProgress.idl
new file mode 100644
index 000000000000..3f3cdf5cb173
--- /dev/null
+++ b/xpinstall/public/nsIXPInstallProgress.idl
@@ -0,0 +1,30 @@
+/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ *
+ * The contents of this file are subject to the Netscape Public License
+ * Version 1.0 (the "NPL"); you may not use this file except in
+ * compliance with the NPL.  You may obtain a copy of the NPL at
+ * http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the NPL is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
+ * for the specific language governing rights and limitations under the
+ * NPL.
+ *
+ * The Initial Developer of this code under the NPL is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
+ * Reserved.
+ */
+
+#include "nsISupports.idl"
+
+[uuid(eea90d40-b059-11d2-915e-c12b696c9333)]
+interface nsIXPInstallProgress : nsISupports
+{
+        void BeforeJavascriptEvaluation();
+        void AfterJavascriptEvaluation();
+        void InstallStarted([const] in string UIPackageName);
+        void ItemScheduled([const] in string message );
+        void InstallFinalization([const] in string message, in long itemNum, in long totNum );
+        void InstallAborted();
+};