QoS-based service selection mechanisms will play an essential role in service-oriented architectures, as e-Business applications want to use services that most accurately meet their requirements. However, current techniques provide no support for actually making rational selections. In this paper, we develop a multiagent framework for QoS-based Web services selection, through a combination of the respective merits of agent and service-oriented to enables dynamic and efficient delivery of composite Web services. We present a service-oriented distributed reputation assessment algorithm as a QoS support module in the framework. We give an example application and some preliminary results.