Statement of Purpose and Method of Study: The purpose of this evaluative case study is to describe and explain how third through fifth grade teachers perceive the implementation of Positive Behavior Interventions and Supports (PBIS) practices on student behavior management within three urban elementary schools in Central Mississippi. The sample included 27 elementary school teachers experienced with the implementation of PBIS at the elementary level at three Central Mississippi urban schools during the COVID-19 pandemic. The Context, Input, Process, and Product (CIPP) model and the Positive Behavior Intervention and Supports (PBIS) were used for conceptual framework. The research questions were guided by the CIPP model, which focused on the perceptions of teachers regarding the need, purpose, strategies, and plan, as well as the fidelity and consistency of PBIS, along with the overall influence of the implementation of PBIS on behavior management. Three sources of data were used in the study: a questionnaire completed at the participant's school, online Zoom interviews, and a PBIS Focus Handbook. There were two rounds of coding, initial coding and axial coding, which were computed and compiled. Findings and Conclusions: The data revealed the effect of the implementation of PBIS on the overall influence of elementary students' behavior management. Some of the results of the implementation of PBIS showed that consistency is needed, rewards are positive motivators for students, and buy-in from others within the school, including teachers, principals, bus drivers, and even cafeteria staff, helps with consistency of student behavior. However, the findings also revealed some negatives which suggested that more PBIS training is needed for all involved. Results also indicated that changing the minds of veteran teachers to implement PBIS using the most up-to-date strategies can be difficult. [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.]