Since the 1990s, K-12 schools across the U.S. have changed in important ways in an effort to maintain safe schools. They have added police officers, surveillance cameras, zero tolerance policies, and other equipment and personnel, while increasingly relying on suspension and other punishments. Unfortunately, we have implemented these practices based on assumptions that they will be effective at maintaining safety and helping youth, not based on evidence. The Real School Safety Problem addresses this problem in two ways. One, it provides a clear discussion of what we know and what we don’t yet know about the school security and punishment practices and their effects on students and schools. Two, it offers original research that extends what we know in important ways, showing how school security and punishment affects students, their families, their schools and their communities years into the future. Schools are indeed in crisis. But the real school safety problem is not that students are either out of control or in danger. Rather, the real school safety problem is that our efforts to maintain school safety have gone too far and in the wrong directions. As a result, we over-police and punish students in a way that hurts students, their families and their communities in broad and long-lasting ways.