Abstract. Web services are increasingly used for building enterprise information systems according to the Service Oriented Architecture (Soa) paradigm. We propose in this paper a tool-equipped methodology allowing the formal modeling and analysis of Web services described in the Bpel language. The discrete-time transition systems modeling the behavior of Bpel descriptions are obtained by an exhaustive simulation based on a formalization of Bpel semantics using the Algebra of Timed Processes (Atp). These models are then analyzed by model checking value-based temporal logic properties using the Cadp toolbox. The approach is illustrated with the design of a Web service for Gps navigation.