In the context of a Web-based organization and of service-oriented processes supporting it, the paper motivates an explicit semantic correlation between the mandatory signature of the activities and the semantics of the services discovered to execute them and, also, of the requests submitted for their execution. An 'activity- service' semantic correlation is proposed as an explicit criterion for enhancing the service semantics related to a process (either for services defined from scratch or already published). This criterion usually exists only in the service or process designers' minds. The 'activity- request' semantic correlation is proposed for the optimization of the request-service matchmaking. The paper also proposes the use of ontology-based templates semantically compatible for activities, services and requests.