On the basis of fieldwork in a temporary staffing agency (TSA), I argue that while temp agencies may provide transitional mobility for jobseekers, in the long run the TSA systematically exploits and reproduces structural vulnerability in the labor market. The agency creates a core of permanent temporary workers separate from the periphery of surplus workers, such that the former is given priority in job allocation. The staffing agency can use alliances with institutions such as private correctional facilities to control its peripheral workers. At the same time, highly valued core workers also face precarious conditions when they are barred from job mobility and their wages are capped. The agency further reinforces precariousness during the moment of work by extending the agency’s surveillance to client sites.