The purpose of this study was to gain an understanding of the perceived impacts of Positive Behavior Supports (PBIS) on high school climate. The research question was how PBIS impacts school climate. Three Indiana schools with different demographic make-ups matching the criteria of having used PBIS for at least three years were chosen for this research. Semi-structured interviews were held with key personnel at all three schools. Emerging themes for factors affecting perceived effects of PBIS were administrative and teacher turnover, administrator and teacher buy-in, principal leadership, and teacher groups and cliques. Implications included implementing PBIS with turnover in mind, garnering buy-in from all stakeholders, the importance of principal leadership, and the importance of a unified staff to increase perceived positive impacts of PBIS on school climate. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]