An emerging literature on school-wide Positive Behavior Support (PBS) in urban settings suggests the utility of PBS in addressing student social development while decreasing the need for disciplinary actions (i.e., office disciplinary referrals [ODRs]). This research represents a significant addition to, and expansion of, this literature by examining the relationship of school-wide PBS-induced reductions in out-of-class referrals to student academic achievement. School-wide PBS was implemented in an urban, inner-city middle school in the Midwest over a 3-year period. Data on ODRs, suspensions, standardized test scores, and treatment fidelity were gathered and analyzed. Results demonstrated significant reductions in ODRs and suspensions and increases in standardized math and reading scores. Additionally, regression analyses suggested a significant relationship between student problem behavior and academic performance. Treatment adherence to PBS procedures was significantly correlated with reductions in problem behavior. These findings are discussed in terms of helping urban schools address challenging behavior. (Contains 1 figure and 3 tables.)