This paper presents a methodology and a set of tools for the modelling, validation and testing of Web service composition, conceived and developed within the French national project WebMov. This methodology includes several modelling techniques, based mainly on some variations of Timed Extended Finite State Machines (TEFSM) formalism, which provide a formal model of the BPEL description of Web services composition. These models are used as a reference for the application of different test generation and passive testing techniques for conformance and robustness checking. The whole WebMov methodology is integrated within a dedicated framework, composed by a set of tools that implement the model representation, the test generation and passive testing algorithms. This framework also permits the interaction of these tools to achieve specific modelling and testing activities in a complementary way. A case study based on a real service, a Travel Reservation Web Service, is presented as well as the results of the application of the proposed WebMov methodology and tools