diff --git a/node_zeromq/zmq-tests.ts b/node_zeromq/zmq-tests.ts
index bb97fd2ca..a982c60d4 100644
--- a/node_zeromq/zmq-tests.ts
+++ b/node_zeromq/zmq-tests.ts
@@ -32,4 +32,6 @@ function test5() {
     sock.bind('tcp://127.0.0.1', err => {
         sock.send("some work");
     });
-}
\ No newline at end of file
+    sock.monitor();
+    sock.monitor(10);
+}
diff --git a/node_zeromq/zmq.d.ts b/node_zeromq/zmq.d.ts
index 7e81dd217..8df3ee8c6 100644
--- a/node_zeromq/zmq.d.ts
+++ b/node_zeromq/zmq.d.ts
@@ -144,6 +144,14 @@ declare module 'zmq' {
         */
         send(msg: any[], flags?: number): Socket;
 
+        /**
+        * Enable monitoring of a Socket
+        *
+        * @param {Number} timer interval in ms > 0 or Undefined for default
+        * @return {Socket} for chaining
+        */
+        monitor(interval?: number): Socket;
+
         /**
          * Close the socket.
          *
@@ -181,5 +189,4 @@ declare module 'zmq' {
     function socket(type: number, options?: any): Socket;
     function createSocket(type: string, options?: any): Socket;
 
-
-}
\ No newline at end of file
+}