Peer review is a method used to inform decision-making by engaging experts in a critical evaluation of the merits of a product or proposal. It is most commonly known as a mechanism for judging the quality of proposals for research funding, or manuscripts submitted for publication in academic journals. It is at once a tool with which scientific judgment is formalized and decisions about the allocation of scarce public resources are legitimized. Strengthening Peer Review in Federal Agencies That Support Education Research seeks to advance an improved understanding of a scientific approach to addressing education problems and to engage the field of education research in action-oriented dialogue about how to further the accumulation of scientific knowledge. The focus of this report is on peer review as it is applied to the evaluation of proposals for federal funding of education research projects.