diff --git a/lib/locallock.js b/lib/locallock.js
index 4826bad..e794819 100644
--- a/lib/locallock.js
+++ b/lib/locallock.js
@@ -9,26 +9,48 @@ function Lock() {
 Lock.prototype._runOne = function(token) {
   var self = this;
 
-  if (locks[token].length == 0) return;
+  var item = _.first(locks[token]);
+  if (!item || item.started) return;
 
-  var task = locks[token][0];
+  item.started = true;
+  if (item.maxRunningTime > 0) {
+    setTimeout(function() {
+      var it = _.first(locks[token]);
+      if (it != item) return;
+      locks[token].shift();
+      self._runOne(token);
+    }, item.maxRunningTime);
+  }
 
-  task(null, function() {
+  item.fn(null, function() {
     locks[token].shift();
     self._runOne(token);
   });
 };
 
 Lock.prototype.locked = function(token, wait, max, task) {
+  var self = this;
+
   if (_.isUndefined(locks[token])) {
     locks[token] = [];
   }
 
-  locks[token].push(task);
+  var item = {
+    maxRunningTime: max,
+    started: false,
+    fn: task,
+  };
+  locks[token].push(item);
 
-  if (locks[token].length == 1) {
-    this._runOne(token);
+  if (wait > 0) {
+    setTimeout(function() {
+      var it = _.find(locks[token], item);
+      if (!it || it.started) return;
+      locks[token] = _.without(locks[token], it);
+      it.fn(new Error('Could not acquire lock ' + token));
+    }, wait);
   }
+  self._runOne(token);
 };
 
 module.exports = Lock;
diff --git a/test/locallock.js b/test/locallock.js
index 7e0b8f5..468511e 100644
--- a/test/locallock.js
+++ b/test/locallock.js
@@ -56,4 +56,33 @@ describe('Local locks', function() {
       done();
     }, 1);
   });
+  it('should return error if unable to acquire lock', function(done) {
+    lock.locked('123', 0, 0, function(err, release) {
+      should.not.exist(err);
+      setTimeout(function() {
+        release();
+      }, 5);
+      lock.locked('123', 1, 0, function(err, release) {
+        should.exist(err);
+        err.toString().should.contain('Could not acquire lock 123');
+        done();
+      });
+    });
+  });
+  it('should release lock if acquired for a long time', function(done) {
+    var i = 0;
+    lock.locked('123', 0, 3, function(err, release) {
+      should.not.exist(err);
+      i++;
+      lock.locked('123', 15, 0, function(err, release) {
+        should.not.exist(err);
+        i++;
+      });
+    });
+    setTimeout(function() {
+      i.should.equal(2);
+      done();
+    }, 10);
+  });
+
 });