Ecosystem Service Assessments (ESAs) have become a popular tool for science-based policy. Yet, there are few guidelines for developing an ESA to inform a decision-making process. This is an important area of inquiry since the process of conducting an ESA is likely to affect the quality of results and their influence on decisions. Drawing on the lessons of conducting ESAs around the world, we propose a set of enabling conditions and a framework for carrying out ESAs that foster high-quality results and drive action. Our framework includes an emphasis on iterative stakeholder engagement, advancing science to address policy needs, and capacity-building through six general steps: (1) scope the process, (2) collect and compile data, (3) develop scenarios, (4) analyze ecosystem services, (5) synthesize results, and (6) communicate knowledge. Our experience indicates that using this framework to conduct an ESA can generate policy-relevant science and enhance uptake of information about nature ’ s benefits in decisions.