Nowadays, most of the approaches for compositions of web services are focused on feasibility of implementation rather than on satisfying business concerns. Meeting business concerns also demands flexible and agile implementations. We present an approach for service composition based on the lifecycle of e-contract. Econtracts have clauses and rules that express business concerns on how services are offered and consumed. We propose an architecture that enables the automation of implementation of composite services. The automation is on the configuration of web service engines. The architectural model supports the publication of contracts that describe how services are offered from different providers in order to develop the composition of services.