Modeling the enterprise from different views, at different levels of abstraction, and in different modeling languages yields a variety of models. Oftentimes the models referring to the same subject exist independently of each other and their semantic relations are hard to discover or to analyze. This fact hinders the effective exploitation of enterprise models for the purpose of integration and interoperability. The method proposed in this paper is based on semantic annotations and aims for the externalization and machine readability of the model contained information. This assures the accessibility for further automatic processing and facilitates the discovery and analysis of inter-model relations.