More resources are being poured every year into efforts to broaden participation in STEM, and foundations and other resource providers need up-to-date evidence about what works in shaping individual and organizational outcomes. This report introduces such evidence, toward enabling the Alfred P. Sloan Foundation to develop the wisest investments in STEM graduate education. We present findings from a systematic review of 228 recently published research manuscripts and evaluation reports about efforts to advance diversity, equity, and/or inclusion by race, gender, and other social identities in STEM graduate education.