What evidence supports the call for discipline reform? How might alternative strategies affect students and schools? In this article, the authors describe the critiques of exclusionary discipline and then examine the research base on which discipline policy reform rests. They also describe the alternative approaches that are gaining traction in America's schools and present the evidence on their efficacy. Throughout, they consider what they know (and don't yet know) about the effect of reducing suspensions on a variety of important outcomes, such as school safety, school climate, and student achievement. In general, they find that the evidence for critiques of exclusionary discipline and in support of alternative strategies is relatively thin. In part, this is because many discipline reforms at the state and local levels have only been implemented in the last few years. While disparities in school discipline by race and disability status have been well documented, the evidence is inconclusive as to whether or not these disparate practices involve racial bias and discrimination. Further, the evidence on alternative strategies is mainly correlational, suggesting that more research is necessary to uncover how alternative approaches to suspensions affect school safety and student outcomes.