PROJECT SUMMARY Permanent supportive housing (PSH), the gold standard intervention for ending chronic homelessness, has expanded rapidly across the U.S. in recent years and is likely to continue expanding as homelessness increases in the wake of the COVID-19 pandemic. Due to a confluence of individual and environmental risk factors, PSH tenants face heightened risk for overdose (OD). While evidence-based practices (EBPs) to prevent OD exist, they have not been broadly implemented in PSH settings. We propose to address this significant research to practice gap by tailoring a set of evidence-based OD prevention practices for PSH settings, then studying their implementation in 20 PSH buildings in New York. We will test a package of implementation strategies that includes an implementation toolkit, tenant-staff implementation champion dyads, limited practice facilitation, and learning collaboratives. The project will be conducted in partnership with the Corporation for Supportive Housing, a national organization that advances solutions to improve PSH through education, practice, and policy. Aim 1 is to adapt evidence-based OD prevention practices for PSH, using key stakeholder focus groups, and develop a PSH OD Prevention Toolkit to guide implementation. In this preparation phase we will adapt an existing package of EBPs in consideration of the unique environmental characteristics of PSH and will prepare for implementation. Aim 2 is to evaluate implementation of evidence- based OD prevention practices across diverse PSH buildings and effectiveness on PSH tenant outcomes in a stepped wedge trial. In this Hybrid Type 3 effectiveness-implementation study, the primary implementation outcome is PSH building adoption of the OD prevention EBPs. We will additionally examine secondary implementation outcomes, tenant clinical outcomes, and implementation sustainment. Aim 3 is to explore multilevel factors influencing implementation—including barriers and facilitators—and refine dissemination and implementation frameworks for housing settings, using qualitative interviews with PSH staff. The research draws from the EPIS (Exploration, Preparation, Implementation, Sustainment) implementation framework and Rhodes’ Risk Environment Framework. The research will inform implementation frameworks and strategies by examining application of EPIS for PSH and testing novel housing-relevant implementation strategies including staff-tenant implementation champion dyads. Findings from this PSH-focused research are expected to be more broadly applicable to other types of housing and settings serving people experiencing homelessness. The multidisciplinary investigator team will work with a Stakeholder Advisory Board to maximize impact of the research, which has been designed to inform local and national programmatic and policy interventions. Changes in the epidemiology of the U.S. OD crisis highlight the need for concerted efforts to reduce the disparate burden of ODs faced by ...