Importance Homelessness is a persistent and growing problem. What role health systems should play and how that role is incorporated into larger strategic efforts are not well-defined.

Objective:

To compare homelessness among veterans with that in the general population during a 16-year study period before and after implementation of the Ending Veteran Homelessness Initiative, a program to rehouse veterans experiencing homelessness. Design, Setting, and

Participants:

This national retrospective cohort study using a mixed-methods approach examined annualized administrative (January 1, 2007, to December 31, 2022) and population data prior to (2007-2009) and during (2010-2022) the Ending Veteran Homelessness initiative. Participants included unhoused adults in the US between 2007 and 2022. Exposure Enrollment in Veterans Health Administration (VHA) Homeless Program Office components providing housing, case management, and wrap-around clinical and supportive services. Main Outcomes and

Measures:

Point-in-time (PIT) count data for unhoused veterans and nonveterans during the study period, number of Section 8 housing vouchers provided by Housing and Urban Development-Veterans Administration Supportive Housing, number of community grants awarded by Supportive Services for Veterans and Families, and total number of veterans housed each year. Semistructured interviews with VHA leadership were performed to gain insight into the strategy.

Results:

In 2022, 33 129 veterans were identified in the PIT count. They were predominantly male (88.7%), and 40.9% were unsheltered. During the active years of the Ending Veteran Homelessness initiative, veteran homelessness decreased 55.3% compared with 8.6% for the general population. The proportion of veterans in this cohort also declined from 11.6% to 5.3%. This change occurred during a shift to "housing first" as agency policy to create low-barrier housing availability. It was also coupled with substantial growth in housing vouchers, grants to community partner agencies, and growth in VHA clinical and social programming to provide homeless-tailored wrap-around services and support once participants were housed. Key respondent interviews consistently cited the shift to housing first, the engagement with community partners, and use of real-time data as critical. Conclusions and Relevance In this cohort study of the federal Ending Veteran Homelessness initiative, after program implementation, there was a substantially greater decrease in homelessness among veterans than in the general population. These findings suggest an important role for health systems in addressing complex social determinants of health. While some conditions unique to the VHA facilitated the change in homelessness, lessons learned here are applicable to other health systems.