How can Results-based Financing (RBF) help overcome market barriers to modern energy services? Which approaches and design features work best in which circumstances and why? In a brand new report, EnDev shares its lessons learnt from implementing 17 projects across 14 countries in Africa, Asia and Latin America. After seven years of piloting a portfolio of highly diverse RBF approaches covering a wide range of modern energy technologies, EnDev has learned a lot. RBF has proven to be a cost-efficient means of nudging the private sector to deliver energy access services at a large scale, at better quality and in a sustainable manner. It is now time to harvest the fruits of all the implementation experiences made. With this new flagship report, EnDev is sharing a final review of lessons learnt from the EnDev RBF Facility financed by UK Aid. It includes insights from working with the private sector in various partner countries and across various sectors like solar energy, hydro power, biogas and cookstoves. The report is targeted at anyone interested in setting up RBF projects in the energy access sector. As such, it provides recommendations for deciding on RBF as an instrument, planning RBF projects, designing incentive schemes and finally implementing them successfully. Lessons and recommendations on selected topics, such as pro-poor approaches or adaptive management practices, are enriched by practical experiences from the field. These are presented in designated project example boxes. The highlight of the report is a concise summary of major success factors that EnDev has identified along its seven-year learning journey.