In our society, unwanted situations occur daily. To ensure public safety and security, incidents need to be prevented, suppressed or handled as quickly as possible. An adequate awareness of the situation plays a critical role for the different parties involved. The goal of surveillance is to support police officers and other users in the task of identifying potential incidents by supplying this awareness. In this paper advantages of intelligent sensor networks for surveillance tasks are given, with a special attention to different tasks, techniques, added value and future developments. First, the current state-of-the-art for surveillance, and the different needs for information of different persons is discussed. After that, we zoom in on two possible tasks, which can be performed automatically or semi-automatically within the intelligent sensor network: tracking of persons and detection of deviant behaviour. Finally, possibilities are provided for future developments concerning surveillance based on an intelligent sensor network..