Based on the Individuals with Disabilities Education Act (IDEA) mandates, weakened climate/culture, decreased academic scores, and endangered job security, the implementation of a successful behavioral intervention program within the school setting was a necessity (Homer & Sugai, 2000). Quantitative data were obtained from two assessment tools, the School-wide Evaluation Tool (SET) and the School Climate Assessment Instrument (SCAI). To determine the levels of implementation of Positive Behavior Interventions and Supports (PBIS), and if there were significant differences in the levels of the participating schools' climate and culture, the following research questions were answered: (a) What is the level of implementation of Positive Behavior Interventions and Supports in the selected schools over a three-year period? (b) Were there any significant differences in the levels of climate/culture amongst the selected schools? The population of the study came from the faculty of four elementary schools in northern Louisiana. To protect the anonymity of the schools, the participating schools were listed as Schools A through D. According to the General Index obtained from the SET, each of the four schools had satisfactory levels (for the school years of 2012-13, 2013-14, and 2014-15) of PBIS implementation, however it was noted that there were significant differences amongst all four schools in each dimension of the SCAI. Building level administrators can benefit from the findings of this study. Building level administrators should guide their schools with the knowledge that consistent PBIS implementation and a positive climate/culture can provide progressive changes. [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.]