Abstract
The dynamic nature of environnments in which Web services are executed require that these ones must be reactive and adaptive in order to meet changing requirements. These changing requirements have to be taken into account in the Web service composition process. BPEL (Business Process Execution Language), the de-facto standard language used to define processes through the composition of Web services, doesn't support dynamic changes. Therfore, BPEL dosen't support the dynamic adaptation of Web service composition according to the context. In this paper, we propose solution in order to support the dynamic adaptation of service composition through BPEL.