Web services received significant attention recently and several important web service platforms such as .NET are now available. The testing and evaluation of web services are important for both service providers and subscribers. This paper proposes an XML-based object-oriented testing framework Coyote to test web services rapidly. Coyote consists of two parts: test master and test engine. The test master allows testers to specify test scenarios and cases as well as performing various analyses such as dependency analysis, completeness and consistency, and converts WSDL specifications into test scenarios. The test engine interacts with the web services under test, and provides tracing information. The test framework incorporates concepts from object-oriented application frameworks so that it is relatively easy to change test scenarios/cases. Due to the distributed nature of web services, Coyote focuses on integration testing instead of module testing.