In February 2016, the City and County of Denver and eight private investors closed on the city’s first social impact bond, an $8.6 million investment to fund a supportive housing program for 250 of the city’s most frequent users of the criminal justice system. The city will make outcome payments over five years based on the initiative’s goals of housing stability and a decrease in days spent in jail by participants. This report discusses the process that partners developed to refer eligible people to the supportive housing program as well as the challenges and successes of engaging participants throughout the housing lease-up process in the first three-and-a-half years of the program. It also looks at housing stability and jail stays among participants.