Service composition is becoming the dominant paradigm for developing Web service applications. It is important to ensure that a service composition complies with the requirements for the application. A rigorous compliance checking approach usually needs the requirements being specified in property specification formalisms such as temporal logics, which are difficult for ordinary software practitioners to comprehend. In this paper, we propose a property pattern based specification language, named PROPOLS, and use it to verify BPEL service composition schemas. PROPOLS is easy to understand and use, yet is formally based. It builds on Dwyer et al.’s property pattern system and extends it with the logical composition of patterns to accommodate the specification of complex requirements. PROPOLS is encoded in an ontology language, OWL, to facilitate the sharing and reuse of domain knowledge. A Finite State Automata based framework for verifying BPEL schemas against PROPOLS properties is al...