Evidence is growing that housing, a social determinant of health, is an important factor in the health status of various populations. According to the Department of Housing and Urban Development (HUD), more than 610,000 people experience homelessness in the U.S., and over 250,000 individuals within that population have a severe mental illness or a chronic substance use disorder. A new Alliance toolkit, “The Connection between Health and Housing: The Evidence and Policy Landscape,” provides a detailed look into federal, state and local initiatives, as well as cost implications for health and housing programs.