As the number and variety of interconnected sources of agricultural innovations have continued to grow and evolve, so too have the demands for meaningful evidence of both the total payoff and the specific impacts of individual research providers. Important policy and practical funding decisions require a clear understanding of the shares of the overall benefits from investments in R&D attributable to domestic versus foreign and public versus private agencies, or even to individual agencies, as well as the total benefits accruing from innovation. This report provides a detailed economic assessment of the magnitude and sources of the economic benefits to Brazil since the early 1980s from varietal improvements in upland rice, edible beans, and soybeans—crops that span a range of interests from domestic (or even more localized) food security concerns, as with rice grown in typically rainfed, upland production systems, to crops with important international trade implications such as soybeans. The authors of this study pay particular attention to isolating the benefits from genetic improvement, distinct from other factors that change grain yield or quality. They use detailed information of the genetic and breeding histories of each crop and the institutional arrangements for more contemporary crop-improvement research in Brazil to attribute parts of the overall benefits to the research done by various agencies within Brazil, in particular the Brazilian Agricultural Research Corporation (Embrapa, Empresa Brasileira de Pesquisa Agropecuária). Notably, the balance of local versus international spillin contributions to the improvement of each crop is sensitive to the particular crop and time period under consideration. Moreover, the estimated returns to research are especially sensitive to approaches taken to account for the multiplicity of past and present research providers involved in Brazilian crop improvements. Ignoring the efforts of others results in markedly upward-biased estimates of the returns to Embrapa research. Importantly though, even after attributing the overall benefits among the myriad of research providers, the returns to investments in Embrapa research on the three study crops are still substantive. As well as providing new and important evidence on Embrapa’s crop-improvement programs and their payoffs, this report provides more general insight into the importance of addressing attribution questions in evaluating public research investments, develops some methods for doing so, and illustrates how to apply them.