Agriculture projects often focus on improving productivity and farm income to reduce poverty, curtail hunger, and promote environmental sustainability. Over the past decade, growing attention to aid effectiveness has increased emphasis on demonstrating measurable impacts on people and their environment. This interest in learning what is effective in promoting agricultural development has created a challenge for evaluation research and practice, as well as an opportunity to gain knowledge from a relatively young but growing body of impact evaluation work. This Independent Evaluation Group (IEG) meta-analysis examines the results of agricultural impact evaluations around the world—by diverse individuals and groups, including the World Bank—that met standard criteria for design and rigor. The report describes the state of impact evaluation literature in agriculture, provides a taxonomy of agricultural interventions to organize results, and examines discernable performance patterns for lessons to inform the design of future interventions. Worldwide, few evaluations of agricultural interventions use a counterfactual to measure change resulting from the intervention—the majority rely on quasi-experimental or nonexperimental methods. Moreover, the heterogeneity of intervention designs, implementation strategies, and outcome indicators makes it difficult to aggregate results or derive broad conclusions about which interventions work best and under what circumstances. Consequently, the only common denominator for comparing results is whether an intervention has a positive impact on the targeted outcomes. More than half of all intervention types covered in the analysis had positive impacts on various agricultural outcome indicators (mostly yields, income, or input use). Interventions that sought to improve yields or farm income by addressing market-linkage failures, easing access to technologically enhanced inputs, and promoting farmer knowledge through advisory services had the highest share of positive impacts. Impact evaluations of World Bank-supported interventions accounted for one-quarter of the evaluations covered by the analysis; of these, two-thirds had positive impacts on various agricultural dimensions. Land titling and extension services were the most common of these interventions