This article provides an overview of restorative justice (RJ) in US K-12 schools, discusses implementation challenges, and summarizes the most recent two decades of quantitative studies regarding the effectiveness of RJ at achieving a range of outcomes. While RJ has become increasingly popular, there is still relatively little quantitative research regarding its effectiveness. Still, available evidence suggests that RJ programs can improve school climates and reduce student misbehavior and school discipline. Results are more mixed regarding RJ's impact on bullying, student absenteeism, and academic performance.