This paper proposes an extensive reuse approach for SOM, which utilizes a multi-facets ontology system supporting reuse of various service-oriented assets, such as business processes, collaboration templates and services. The paper also presents an iterative service-oriented modeling process based on the ontology and assets repository, which reuses assets from the first to last modeling phase by matching between assets descriptions, and results in a service model that represents the specification of the required service-oriented application.