We claim that user preferences are a key component of Web service composition – a component that has largely been ignored. In this paper we propose a means of specifying and intergrating user preferences into Web service composition. To this end, we propose a means of performing automated Web service composition by exploiting generic procedures together with rich qualitative user preferences. We exploit the agent programming language Golog to represent our generic procedures and a first-order preference language to represent rich qualitative temporal user preferences. From these we generate Web service compositions that realize the generic procedure, satisfying the user’s hard constraints and optimizing for the user’s preferences. We prove our approach sound and optimal. Our system, GologPref, is implemented and interacting with services on the Web. The language and techniques proposed in this paper can be integrated into a variety of approaches to Web or Grid service composition.