This article focuses on the development and implementation of primary and secondary behavior supports at a schoolwide level. The approach described is consistent with previous efforts to address behavior at a systems level (e.g., G. Sugai, R.H. Horner, & F.M. Gresham, 2002). In this article, we illustrate this process through a school-based example. This example is drawn from a larger project in which area regional school-district consultants and university researchers partnered with four elementary schools in an effort to enhance each school's capacity to implement evidence-based practice and decisions at primary (i.e., universal or school-wide), secondary (i.e., targeted efforts for selected groups of students and/or settings), and tertiary (i.e., individual-student) levels to promote behavioral competence. The project incorporated promising strategies and tools designed to promote and sustain the use of evidence-based practices and data-driven problem solving. Continuous progress monitoring of systemic variables and student behavioral outcomes (e.g., office-referral data) helped to guide systemic reform efforts. Reductions were noted in the number of student discipline problems, and improvements were noted in critical features of school-wide effective behavior support at a systems level. Results are discussed with an emphasis on implications for practice, lessons learned from this project, and directions for additional research. (Contains 2 figures and 2 tables.)