This article examines the contemporary role of the police in patrolling the nation’s territorial and social borders. The police play an important role in framing ideas and perceptions of order and disorder. By selecting when and against whom to apply coercion, the police not only constitute crime and criminals. They shape the boundaries of civility and patrol the margins of citizenship. Such role has been revitalized lately as they are tasked with immigration enforcement functions. Drawing on an empirical examination of immigration–police cooperation in England, I explore how police and immigration officers define the remits of their job and work alongside each other in everyday policing. I argue that the reliance on immigration enforcement by the police evinces the limitations of modern policing to decipher the new geographies of crime and disorder, and their difficulties in offering a reassuring response to public anxieties and ultimately in producing social order.