Despite a high level of interest and investment in "gold standard" evaluations of interventions in education, the gap between teaching practice and the latest research on learning appears wider than ever; likewise, persistent attainment gaps between certain groups remain. This report summarizes the presentations and discussion from a roundtable event that brought together representatives from educational practice, research, and policy to explore challenges and solutions in relation to establishing "what works" in different educational contexts. The commentary addresses issues surrounding (a) who is involved and when, (b) a need for methodological innovation, (c) communication, and (d) understanding and use of evidence by educators and policymakers. Suggestions for best practice in relation to addressing these issues using national and international examples are presented. Identified recommendations related to facilitating a research culture within the teaching profession, the promotion of data sharing and communication, and conducting realistic evaluations. Outstanding questions are highlighted.