Individuals with a serious mental illness, especially those who have experienced homelessness, have high rates of medical comorbidities and early mortality. Our “housing first” program combines supported housing, assertive community treatment (ACT), and primary care in order to address these complex service needs. The program began in October 2008 and serves 125 individuals who have met the federal definition of chronic homelessness and have an axis I diagnosis of serious mental illness. Two separate city departments in Philadelphia, the Office of Supportive Housing and the Department of Behavioral Health, made the program possible. U.S. Department Housing and Urban Development funds (Shelter plus Care) provide housing