PROJECT SUMMARY/ABSTRACT Early exposure to Adverse Childhood Experiences (ACEs), such as parental substance use, increases the likelihood of future substance use and drug overdose, resulting in an intergenerational cycle of substance- related ACEs that can continue indefinitely if left uninterrupted. Community-level interventions may moderate the relationship between ACEs and substance use by providing an array of family support services and treatments to reduce disparities and improve reach and service linkages in the community. Although research suggests that effectively decreasing the prevalence and impact of ACEs and substance use requires addressing both family- and community-level factors in tandem, there is a critical gap within the evidence base pertaining to interventions that effectively integrate the two factors to prevent substance use and ACEs. RTI International and its established partners, the New Jersey Prevention Network and RWJBarnabas Health, will evaluate an intervention integrating New Jersey’s established, evidence-based Strengthening Families Program (SFP) with clinically trained, trauma-informed Family Advocates (FAs) who will assist families in accessing community resources. Specifically, this study will use a Hybrid Type 1 effectiveness-implementation design across 20 New Jersey communities experiencing a disproportionate burden of substance use and ACEs to address the Research Objective: Conduct rigorous evaluations of prevention approaches implemented within communities that incorporate efforts to mitigate the harms of ACEs exposure and prevent future ACEs, while aiming to prevent substance use and overdose. The study has three aims: (1) use a cluster randomized controlled trial to test effectiveness of the SFP+FA intervention on substance use, overdose, and ACEs in 10 communities compared with SFP only in 10 communities; (2) conduct a robust process evaluation informed by the Consolidated Framework for Implementation Research to explore implementation barriers and facilitators; and (3) conduct a cost evaluation to accurately estimate the costs required to implement SFP and SFP+FA and assess the cost- effectiveness of SFP+FA relative to SFP alone. Findings will provide a roadmap about the best ways to help disproportionately affected communities prevent substance use, overdose, and ACEs.