A Business Process Model is called rule-based if the logic of its control flow, data flow and resource allocation is declaratively expressed by means of business rules. Business rules are recognized as powerful representation forms that can potentially define the semantics of Business Process Models and business vocabulary. To date, however, there is little consensus and fragmentary knowledge about the precise relationship between these elements of business modeling. In this paper, the authors develop a first-version meta-model that is to be used as a foundation in integrating and developing existing and new forms of rule-based Business Process Modeling. In addition, they show how rule-based process models can be brought to execution in the context of Service-Oriented Architecture.