diff --git a/cometd/cometd.d.ts b/cometd/cometd.d.ts
new file mode 100644
index 000000000..6002fffb0
--- /dev/null
+++ b/cometd/cometd.d.ts
@@ -0,0 +1,28 @@
+// Type definitions for CometD 2.5.1
+// Project: http://cometd.org
+// Definitions: https://github.com/borisyankov/DefinitelyTyped
+
+declare module CometD {
+
+    var onListenerException: (exception: any, subscriptionHandle: any, isListener: boolean, message: string) => void;
+
+    function init(options: ConfigurationOptions): void;
+
+    function addListener(channel: string, listener: (message: any) => void): void;
+    function removeListener(listener: (message: any) => void): void;
+
+    function publish(channel: string, message: any): void;
+
+    interface ConfigurationOptions {
+        url: string;
+        logLevel?: string;
+        maxConnections?: number;
+        backoffIncrement?: number;
+        maxBackoff?: number;
+        reverseIncomingExtensions?: boolean;
+        maxNetworkDelay?: number;
+        requestHeaders?: any;
+        appendMessageTypeToURL?: boolean;
+        autoBatch?: boolean;
+    }
+}