Pursuant to a congressional request, GAO reviewed the Department of Energy's (DOE) "Success Stories" report, focusing on whether the: (1) report's claims are valid; and (2) report can be used to assess DOE applied research and development programs. GAO found that the report: (1) includes supportable claims for benefits stemming from some DOE research; (2) includes mathematical errors, poor economic reasoning and assumptions, and weak, indirect, or false links between benefits and DOE applied research and development programs; and (3) cannot be used to evaluate DOE research and development programs because it lacks sufficient information about program costs to determine cost-effectiveness and is not representative of all DOE applied research and development.