diff --git a/socket.io/socket.io-tests.ts b/socket.io/socket.io-tests.ts
new file mode 100644
index 000000000..841266610
--- /dev/null
+++ b/socket.io/socket.io-tests.ts
@@ -0,0 +1,10 @@
+import io = require('socket.io');
+
+var socketManager = io.listen(80);
+
+socketManager.sockets.on('connection', socket => {
+	socket.emit('news', { hello: 'world' });
+	socket.on('my other event', data => {
+		console.log(data);
+	});
+});
\ No newline at end of file
diff --git a/socket.io/socket.io.d.ts b/socket.io/socket.io.d.ts
index d20b0540a..2b44ff6ab 100644
--- a/socket.io/socket.io.d.ts
+++ b/socket.io/socket.io.d.ts
@@ -40,7 +40,7 @@ interface SocketNamespace {
 	json: any;
 	volatile: any;
 	in(room: string): SocketNamespace;
-	on(evt: string, fn: Function): SocketNamespace;
+	on(evt: string, fn: (socket: Socket) => void): SocketNamespace;
 	to(room: string): SocketNamespace;
 	except(id: any): SocketNamespace;
 	send(data: any): any;