We present the concept of a system architecture for the computer aided craniofacial surgery. The architecture is based on CORBA, an industrial standard specification for the development of distributed applications. Our concept includes a fundamental behaviour oriented communication model and some fundamental software safety considerations. We've developed a standard library for the integration of new services and devices into our system architecture. It decreases development time noticeably. We tested the performance and usability of our concept on an evaluation set up consisting of a surgery robot system, an infrared navigation system, a force-torque sensor and a visualisation software, obtaining excellent results. Future work will consist in the integration of further devices and the extension of our safety concept. An accurate clinical evaluation will take place continuously.