Today, advanced technical systems are complex, reconfigurable mechatronic systems where most control and reconfiguration functionality is realized in software. A number of requirements have to be satisfied in order to apply the model-driven development approach and the UML for mechatronic systems: The UML design models must support the specification of the required hard real-time event processing. The real-time coordination in the UML models must embed the continuous control behavior in form of feedback-controllers to allow for the specification of discrete and continuous hybrid systems. Advanced solutions further require the dynamic exchange of feedback controllers at run-time (reconfiguration). Thus, a modeling of rather complex interplays between the information processing and the control is essential. Due to the safety-critical character of mechatronic systems, the resulting UML models of complex, distributed systems and their real-time behavior must be verifiable in spite of the complex structure and the embedded reconfigurable control elements. Finally, an automatic code synthesis has to map the specification correctly to code. In this paper, we will present our Mechatronic UML approach, which fulfills all these requirements. The approach is motivated and illustrated by means of a running example.