Agroforestry systems have enormous potential to mitigate climate change. These systems incorporate trees and shrubs into agricultural production, increasing both soil carbon sequestration and the amount of carbon stored in biomass. Even the most conservative estimates find that agroforestry sequesters two to five times more carbon per acre than the most effective—and better- known—climate-friendly practices for annual crops, such as no-till agriculture and cover crops. Agroforestry also offers substantial environmental and economic benefits: clean water, reduced fertilizer and pesticide use, greater resiliency, and higher profitability per acre. Yet there are significant legal and policy barriers to its expansion in the United States. For the first time in the policy literature, this Article reviews the emerging scientific research on agroforestry. The Article then analyzes how federal programs for agricultural loans, subsidies, research, and education favor annual monocultures over agroforestry practices. It concludes with a comprehensive set of reforms designed to expand agroforestry.