The purpose of this mixed-methods single case study was to identify the perceived influence of a teacher mentoring program on participants' professional development and retention in the education profession at a small school district in the Southeastern United States. This study sought the perspectives of mentors, mentees, and building administrators to identify the beliefs, characteristics, and aspects of the program deemed most effective in providing development and support to participants. Mentees were also surveyed to determine if there were significant differences in mentorship effectiveness ratings between novice and veteran mentees and between primary and secondary grade-level mentees. This study involved a purposive sample of 11 certified educators currently in the mentoring program who served as building administrators (N = 3), mentors (N = 3), or mentees (N = 5). The study also included a criterion sample of 74 educators who had participated in the mentoring program as a mentee. Qualitative data collection consisted of semi-structured interviews, while quantitative data collection included an anonymous online survey. Common themes identified regarding the perceptions of the mentoring program's influence on educators' professional development were Beneficial to the Mentor, Evaluation Process, Personalized, and Reality Versus Preparation Programs. Common themes identified regarding the perceptions of the mentoring program's influence on educator retention were Acclimation, Connectedness, and Support. The online survey results suggested a small but significant difference between novice (N = 21) and veteran (N = 52) educators' mentorship effectiveness ratings (t = -2.32, p = 0.023). The online survey results also revealed that a significant difference did not exist between the average mentorship effectiveness ratings of primary grade-level (N = 34) and secondary grade-level (N = 40) mentees (t = 0.849, p = 0.399). It was determined that replicating this study across multiple school districts would be required to enhance the generalizability of the findings. The small sample size underscores the need for further research within individual schools in District A to inform and validate best practices for each school in the district. Finally, implications for practice included recommendations for a tailored mentor guidebook, yearly mentor training, adjustment of the program's timeline, and yearly program evaluation. [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.]