This paper presents how conversations are integrated into Web services composition. While much of the recent work on Web services has focussed on low-level standards for publishing, discovering, and triggering them, this paper promotes Web services to the level of active components. Such components engage in conversations, make decisions, and adjust their behavior according to the context of the situations in which they participate. Conversations between Web services are specified with state chart diagrams enhanced with context-awareness mechanisms. © Springer-Verlag Berlin Heidelberg 2005.