School violence can be understood as any behavior that is intended to harm other people at schools or near school grounds. This may include bullying and victimization, or more severe forms of violence involving weapons. To respond effectively to school violence, school personnel and leaders must understand the influences on their schools that come from individuals, the surrounding community, and cultural and political spheres. Careful and ongoing assessment of the needs of any given school is also a prerequisite to effective intervention. The severity of violence, the exact location of violent acts, and how different groups on a school campus experience violence are all key details to understanding and measuring problems. With this information, schools are then able to choose intervention programs that will utilize a whole-school approach. Sometimes, existing Evidence Based Programs can address the needs of a particular school and surrounding community. Other times, schools need to either modify existing interventions or create their own to address the particular forms of violence that exist in their schools and communities.