For many companies, the strategic as well as the organizational fit of their information systems is a pivotal factor for staying competitive. At the same time, there is an increasing demand for integrating business processes and informations systems with those of customers and suppliers. The resulting need for organizational changes and the introduction of corresponding information systems is a challenging task. Enterprise models provide various abstractions that help with the design of corporate information systems which are in line with a company's organization and its long term strategy. They also provide a common conceptual foundation to foster the communication between people with different professional backgrounds. In this paper a method for enterprise modelling is introduced that is based on an extendable set of special purpose modeling languages, e.g., for describing corporate strategies, business processes, resources or information. The visual languages provide intuitive abstractions for various observers. The languages share common concepts which allow for a tight integration of the various parts of an enterprise model. In addition to offering specialized modeling languages, the modeling method also includes examples, case studies and reference models - to promote the re-use of concepts and artefacts. The use of the method is illustrated by an example, where two different partial models are being integrated.