This contribution describes a rule-based method for modeling business processes and workflows. Business rules are defined
as statements about guidelines and restrictions with respect to states and processes in an organization. After introducingan extended Event-Condition-Action (ECA) notation, an approach for the refinement of business rules is developed in orderto achieve a consistent decomposition of the business processes. Thus, ECA rules serve as an integration layer between differentprocess modeling and (workflow) specification languages. Finally, we propose an architecture of a rule-oriented repositorysupporting the modeling and refinement process.