Drug criminalization is associated with a range of poor health outcomes, such as overdose. Without access to adequate housing, people who use drugs (PWUD) experiencing homelessness are more likely to use drugs in public, and thus are among the most impacted by criminalization. Recent changes to BC’s decriminalization policy re-criminalizing drug use in most public spaces (e.g., parks, sidewalks in front of buildings) will likely have significant implications for the health and wellbeing of unhoused PWUD. This study will examine how emerging re-criminalization impacts health outcomes, including overdose, for unhoused PWUD, and will develop novel approaches to community-based research in rapidly changing policy contexts. Research activities include interviews with unhoused PWUD and outreach service providers, observation in community settings, and analysis of text sources (e.g., policy guidance, press releases) to fully understand topic scope. By understanding the dynamic relationship between drug re-criminalization and overdose vulnerability for people experiencing homelessness, this research will generate ideas to guide future drug policy in BC, and that are scalable and adaptable to other settings pursuing drug policy reform.