This brief describes how one county government—Cuyahoga County, Ohio—used an integrated data system (IDS) to develop an innovative pay for success program to serve homeless mothers who have children in the child welfare system. The Cuyahoga program, called Partnering for Family Success, is the first county-level program in the United States. The brief provides background about pay for success or social impact bonds, which began in the United Kingdom in 2010. These agreements allow private and philanthropic investors to provide upfront funding to governments to operate and pilot new evidence-based social programs to save money for the government. Pay for success programs are treated as an investment rather than as traditional grants. The brief outlines the challenges faced by the program developers and how IDS helped them design and evaluate the Partnering for Family Success program. The IDS quickly identified eligible families who were involved with separate county departments. Once identified, the program helped remove housing barriers and connected mothers and their children with other resources, such as housing assistance, behavioral health services, trauma support, and case management.