Defining school violence is a difficult task, as what is generally understood as violence depends on cultural, historical and individual aspects. In spite of such difficulty, a systematization of what integrates or not the phenomenon of school violence is possible, and much needed. Only with well established parameters of what school violence is, will it be possible to develop studies comparing results among different schools, regions and periods. With this end in mind, this paper presents definitions of school violence proposed by researchers, organizing the different points of view. A conceptual model of what is accepted as school violence is suggested. This model, in summary, comprehends that when discussing school violence one should define the place where the violent situations occurs, the persons involved, the role they assumed, how were characterized the episodes of violence and if these events had any particularities.