The sustained multi-decade increase in the prevalence of obesity calls for a new approach on addressing this public health concern. The Roundtable on Obesity Solutions (ROOS) (of the National Academies of Sciences, Engineering, and Medicine NASEM), a multisector group comprised of members from a variety of organizations and institutions, initiated a year-long effort to build a strategic plan and roadmap for action that would drive a paradigm shift for the ROOS in pursuing obesity solutions. Following a review of obesity prevention and treatment recommendations with sufficient actionable-evidence by authoritative organizations, the ROOS deployed systems science methods. Members engaged in group model building (GMB) exercises to develop an obesity systems map based on determinants and drivers from a multi-sector perspective and overlaid with aligned solutions. To expand the understanding of systems science approaches and methods, 3 public workshops were held in tandem with the development of the map. The causal map was refined, and solutions were ranked using a leverage-point framework to inform a strategic plan and narrative roadmap for action. For the ROOS, structural racism and social justice, biased mental models and social norms, and effective health communications were prioritized as the leverage points most likely to have a significant impact in addressing obesity. Complementary to the mission, vision, and guiding principles of the ROOS, the obesity systems map, and narrative roadmap will drive the ROOS activities over the next 3-6 years and serve as a resource for researchers, organizations, and institutions involved with policy, prevention, and treatment of obesity.