public void should_get_latest_sermons() { ICollection <Sermon> _results = new List <Sermon>(); Exception _ex = new Exception(); ManualResetEvent done = new ManualResetEvent(false); IGatewayService sut = new GatewayService(); sut.GetLastestSermons((results, ex) => { _ex = ex; _results = results; done.Set(); }); done.WaitOne(); Assert.IsNull(_ex); Assert.IsTrue(_results.Count > 0); }