Increasing the performance and flexibility of automated manufacturing systems is a key success factor for today’s production companies. Flexible Manufacturing Systems (FMS) have proven to be particularly suitable in this regard since they support small lot sizes and high numbers of variants at the same time. The most important problems facing FMS are the huge expenditure of time and the high costs for “engineering” its control software. Engineering in this context refers to all aspects from planning the concrete production process, to assigning machines to control programs, to implementing software modules, and to testing the whole configuration. In this paper, we describe a model driven approach to support consistent engineering of FMS control software. It makes use of UML and customized UML metamodels for FMS-specific features, and includes a prototype implementation based on open source. We report on first experiences with a real FMS running cosmos 4, a distributed, agent-oriented FMS control software.