Over the past two decades, researchers and educators have increasingly recognized the importance of K-12 school climate. This summary builds on our 2009 school climate research summary (Cohen, McCabe, Michelli, & Pickeral, 2009) and details how school climate is associated with and/ or promotes safety, healthy relationships, engaged learning and teaching and school improvement efforts. With a few exceptions, the citations in this issue represent empirical studies that have been published in peer-reviewed journals.