Housing for vulnerable populations—identifying system cost implications: an analytic literature review.

This article reviews 42 peer-reviewed studies examining how investments in housing for vulnerable populations—defined as groups at higher risk of poor health due to social, economic, or environmental barriers—affect cost containment in health, justice, and social service systems. The majority of studies focused on permanent supportive housing (PSH) for adults experiencing chronic homelessness, primarily in the USA, and found that housing interventions generally reduce costs related to hospital and emergency services, justice system involvement, and shelter use, while increasing outpatient and mental health service utilization. Funding for these interventions commonly comes from federal, state/provincial, and municipal sources, with cost savings typically observed in the medium term (1–5 years), though evidence on long-term impacts remains limited. The review highlights the importance of a systems-level perspective to fully capture cost-containment benefits and notes gaps in research on diverse populations and intervention types beyond PSH.