Disparities in behavioral outcomes for minority students are a decades-old problem. Recently, the systems-level approach of school-wide positive behavior support (SW-PBS) and its growing research base have garnered attention as a possible remedy. Although SW-PBS has been shown to be effective in reducing a school's overall level of office discipline referrals (ODRs) and suspensions (OSS), and its success has been replicated in schools with large populations of minority students, effective outcomes across all groups of students within a school are not guaranteed. Some reports document increases in the magnitude of disproportionality even when ODRs and OSS decrease for the school as a whole. However, studies of SW-PBS and disproportionality have overlooked the role of implementation fidelity as a potential mediator of student outcomes, allowing for the possibility that schools that fail to experience a reduction in ODRs and OSS across all groups of students are those in which few elements of SW-PBS have been implemented. The present study contributed to the current research base by investigating whether schools which implement SW-PBS with higher levels of fidelity were more likely to have lower levels of disproportionate ODRs and OSS for African American and Hispanic students. Drawing from online databases which record schools' implementation and ODR information, this study provided detailed school-level descriptive analyses of ODRs and OSS for African American, Hispanic, and White students. Additionally, risk ratios for receiving an ODR and for receiving an OSS were calculated for African American and Hispanic students, and then compared to each school's reported level of SW-PBS implementation as measured by their Benchmarks of Quality score. The descriptive analyses and follow-up Chi-Square analyses revealed that there was no significant relationship between a school's level of implementation fidelity and their magnitude of disproportionality for these groups of students. Implications for professional development, record keeping, and measuring disproportionality in schools are discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]