Critical Time Intervention (CTI) is designed to prevent recurrent homelessness and other adverse outcomes among persons with severe mental illness. It aims to enhance continuity of care during the transition from institutional to community living. The intervention, which lasts roughly 9 months following institutional discharge, involves two components: (1) strengthening the individual’s long-term ties to services, family, and friends; and (2) providing emotional and practical support during the transition. Postdischarge services are delivered by workers who have established relationships with patients during their institutional stay. CTI is intended to be used with individuals leaving institutions such as shelters, hospitals, and jails. The intervention is delivered in three main phases: (1) transition to the community, which focuses on providing intensive support and assessing the resources that exist for the transition of care to community providers; (2) tryout, which involves testing and adjusting the systems of support that were developed in the first phase; and (3) transfer of care, which completes the transfer of care to community resources that will provide long-term support.