This guide is designed to supply educators with a means to identify whether racial/ethnic disproportionality in discipline practice exists in their schools or districts. It also aims to help educators use data to reduce racial/ethnic disproportionality in suspensions and expulsions. The guide is organized into two sections. The first section provides information on how to select, analyze, and interpret data indicators to determine whether disproportionate discipline practices exist and, if an intervention is implemented, to measure progress toward desired outcomes. The first section also describes types of data that can help identify factors that may contribute to disproportionality in school discipline and inform selection of interventions. The second section describes how to use the Plan-Do-Study-Act process to make decisions on improving equitable school discipline practices. Throughout the guide, examples are also provided from Oregon districts that have made reducing racial disproportionality in school discipline a priority. This guide may be useful for local and state education agency administrators, principals, teachers, coaches, behavior specialists, and educators involved in school discipline policies or practices. A list of supportive school discipline websites and resources can be found in the appendix. (This guide was written with Sho Shigeoka and Erin Lolich.)