There is growing attention on place-based systems change approaches to help address complex social problems. There is agreement on the goal of these approaches- to address problems and, ultimately, improve population health outcomes. However, researchers, practitioners, policy-makers and funders grapple with the question of how do we define success at the system level? In this Findings Snapshot, we address this question. Defining success for place-based systems change approaches will help those who fund, design, implement, and evaluate place-based systems change approaches and advance knowledge about the effectiveness of these approaches.