The United Nations Reducing Emissions from Deforestation and Forest Degradation (REDD+) framework is a public climate finance model designed to reduce net global greenhouse gas emissions by conserving forests in developing countries. As one of the world’s most well-funded and widely dispersed structures for investing in nature to counteract global climate change, REDD+ has attracted frequent criticism and debate since its establishment in 2007. Chief among these questions: does REDD+ actually deliver emissions results? If not, why not – and what alternative investment structures could be designed in its place? This project evaluated the effects of investment design – i.e., the selection of objectives, instruments, terms which form an investment contract – on emissions reduction in Brazil’s Amazon, as an entry point for understanding the most effective investment strategies for nature-based climate finance.