Non-suicidal self-injury (NSSI) is a growing concern among professionals working with youth. Recent studies exploring the occurrence of NSSI in middle and high schools indicate that 15% to 20% of students will admit to having engaged in this behavior at least once. The alarming number of adolescents engaging in NSSI poses a challenge to all school-based professionals. This article focuses on the management of NSSI within the schools. Guidelines for responding to NSSI on a personnel and system-level are described, including critical information for school-based professionals working with youth who engage in NSSI. Subsequently, developing policies related to NSSI across the school, such as school-wide prevention, contagion issues, and development of a school response protocol are discussed.