This report summarizes the REDD+ experience over the past decade. It draws on research conducted under the Global Comparative Study on REDD+ by the Center for International Forestry Research to take stock of lessons learned from REDD+ implementation to inform future forest-based climate change mitigation activities. It describes how the idea of REDD+ has evolved through international negotiations and early implementation, while complementary global initiatives have emerged. It analyzes the progress and challenges arising from REDD+ initiatives at national, subnational, and project scales, and concludes with forward-looking recommendations.