Denver sought to provide individuals experiencing homelessness with permanent alternatives to costly emergency services such as hospitals and shelters. As part of the Permanent Supportive Housing Pay for Success initiative, the GPL helped Denver identify the most costly chronically homeless individuals who were also involved with the criminal justice system as candidates for supportive housing. With its project partners, the City is building 160 new units and using 90 existing units to house these individuals and testing the results with a five-year randomized control trial. The evaluation of the program will be one of the longest and most rigorous studies of supportive housing in the country.