Restorative justice is a non-punitive approach to resolving conflict that focuses on restoring relationships. This report summarizes recommendations about future research and evaluation needs that would advance the understanding of restorative justice in K-12 schools in the United States. The recommendations were generated from interviews with over 40 nationally recognized leaders in restorative justice, supplemented by a large focus group discussion, and cover: (1) Implementation readiness; (2) Whole-school versus stand-alone models; (3) Implementation and effectiveness; (4) Impacts on racial and ethnic minorities and students with disabilities; (5) Leadership/training; and (6) Data and measurement. Also included in the report is a starter set of research questions that can be considered by foundations, the federal government, and the research community to begin building a strong body of empirical evidence about restorative justice in schools. An appendix contains the names of the individuals who were interviewed for this report.