Service-oriented architectures, and notably Web Services, are becoming an incontrovertible paradigm for the development of applications in pervasive computing environments, as they enable publishing and consuming heterogeneous networked software and hardware resources. Combined with Semantic Web technologies, in particular ontologies, Web services' descriptions can be unambiguously and automatically interpreted in open pervasive computing environments, where agreement on a single common syntactic standard for identifying service semantics cannot be assumed. Nevertheless, efficient matching of semantic Web services to effectively automate the discovery and further consumption of networked resources remains an open issue, which is mainly attributable to the costly underlying semantic reasoning. After analyzing the cost of ontology-based semantic reasoning, which is at the heart of the matching process, we propose a solution towards efficient matching of semanticWeb services.We have further incorporated our solution into a service discovery protocol aimed at open pervasive computing environments that integrate heterogeneous wireless network technologies (i.e., ad hoc and infrastructure-based networking). Experimental results show that our solution enables better response times than of classical syntactic-based service discovery protocols.