This Coffee Chat will explore how, based on an understanding of the etiology of substance use and other risky behaviors, community-based coalitions can build prevention service systems that can have far-reaching impacts. Effective coalitions are key to having these ‘population-based’ outcomes as they know and represent their broader communities, and have the potential of being more skilled at influencing the allocation of prevention resources, community policies & practices, inter-organizational relationships and community awareness, knowledge, and values