摘要:This article is about the targeted, temporarily intensified use of an already existing, permanently installed surveillance system for the safety and security management during a local event at the campus of the University of Illinois, USA. In particular it is the CCTV system that is analyzed after an ethnographic control room study. It became clear that the law enforcement intensified the use of the CCTV system during the festival. The temporal, intensified use of a surveillance system is in this article labeled as 'liminal surveillance'. Not only could the police intensify the surveillance as a result of the liminal use of the CCTV system, but they also could test the system in extreme circumstances, advocate its use, and raise attention for safety and security issues during the festival. In this article both the intended and unintended consequences of liminal surveillance are discussed.