In Service-Oriented Architectures (SOA), service descriptions are fundamental elements. In order to automatically execute SOA tasks, such as services discovery, it is necessary to capture and process the semantics of services. We review several Semantic Web Services frameworks that intend to bring semantics to Web Services. This chapter depicts some ideas from SOA and Semantic Web services and their application to enterprise application integration. We illustrate an example of logic-based semantic matching between consumer services and provided services, which are described in ontologies.