Elementary schools can play an important role in early identification of and intervention for children with problem behavior by creating the infrastructure to provide preventive, proactive supports for all students. This monograph provides an overview of key features of effective school-wide systems of positive behavior support (PBS) at the elementary school level. It begins by discussing research findings on effective school-wide discipline practices based on PBS. Key features of PBS are described, including the emphasis on prevention and the use of a continuum of supports that focus on increasing appropriate behavior. Policies and procedures that enhance organizational capacity for successful implementation are summarized and include: (1) provide proactive discipline handbooks to educators that detail the behavioral expectations; (2) adopt research-validated practices; (3) build durable systems that include data-based decision making and screening for early intervention, team-based problem solving, and systematic communication; and (4) use systems that enhance behavioral capacity by establishing student support teams and providing staff development. The role of the administrators in the development of a school-wide system of PBS is explained, along with the strategies for establishing a district-wide system of PBS. (Contains 50 references.) (CR)