Abstract—This paper illustrates how the functionalities of monitoring/control systems, within an agent–based framework, can be improved by the adoption of Knowledge–Based techniques. Moreover, the context of Pervasive Computing is chosen as a very promising application domain. After a discussion about the main characteristics a monitoring/control system should have, a possible agent–based architecture for designing this kind of tools is proposed. In particular, it is pointed out how the use of knowledge– based methods is fundamental to provide the systems with the capacity to correlate different perceptions of the reality, in order to obtain more robust, reliable and reasonable system. A possible interpretation of this architecture according to agent theory is given. Finally, a real monitoring/control system based on it is briefly described.