public void Should_CallDependencyWithParameters() { var expectedFirstParameter = "any string"; var expectedSecondParameter = "any other string"; application.ReturnStringWithTwoParameters(expectedFirstParameter, expectedSecondParameter); var parameters = mockService.GetArgumentsForCallsMadeOn(service => service.ReturnStringWithTwoParameters(Arg <string> .Is.Anything, Arg <string> .Is.Anything)); // the method was called once var expectedCallsCountMade = 1; Assert.AreEqual(parameters.Count, expectedCallsCountMade); Assert.AreEqual(parameters[0][0], expectedFirstParameter); Assert.AreEqual(parameters[0][1], expectedSecondParameter); }