Web service orchestration technologies are emerging as practical means to integrate business partners' applications with higher levels of functionality, negligible performance degradation, reduced development effort, and better quality of service. However, because most compositional languages address distribution concerns at the early stage of the business process definition, Web-based applications become more static arid more difficult to develop. In this paper we propose a method to reduce the complexity of Web service orchestration by using a new compositional language named BPCL (business process coordination language) that keeps apart physical distribution details. Furthermore, a coordination architecture has been built to support the common process abstractions used in business collaboration by means of a synchronization and communication infrastructure. In the proposed approach, to obtain a Web-based application, aspect oriented programming is used to weave locality transparent BPCL programs with the distribution handling capabilities supported by the coordination architecture. Besides of simplifying the development of orchestrated Web-based applications, the main contribution of this work consists on providing a coordination language and architecture that promote greater dynamism, noninvasive code reuse and efficient execution.