Web services and software agents share a motivation of aiming to facilitate more flexible and adaptable I.T. systems. Web services are increasingly being used to provide active behaviour over the Internet, and promise end-user benefits that, in previous work, have been associated with agent systems. Thus it is natural to consider what relationships agents should have to web services. We argue that agents and web services are distinct. In our work, agents provide a distinctive additional capability in mediating user goals to determine service invocations. In this paper, we review some of the design choices for integrating agents and web services, and illustrate one approach using reactive planning to control web-service invocation by BDI agents. Notes: Michael Wooldridge, Department of Computer Science, University of Liverpool, Liverpool, UK. 8 Pages