School principals are tasked with a daunting number of responsibilities, all of which must culminate in increased student achievement. The complexity of these responsibilities have left school leaders overwhelmed, resulting in diminished confidence and potentially substandard job performance. This study addressed the problem that many school principals do not possess high levels of self-efficacy for the responsibilities they face as campus leaders. Given that principals significantly impact student achievement, which research links to overall prosperity, an entire community can be negatively impacted by a low-performing principal. The purpose of this quantitative, correlational study was to examine the relationship between mentoring support and increased self-efficacy for management, instructional leadership, and moral leadership for public school principals in south central Texas, while controlling for years of experience. The social cognitive theory was used to frame the study. A convenience sample of participants was recruited from 996 school principals working at traditional public school campuses located in Regions 13 and 20. An email was sent to potential participants consisting of information about the study, informed consent, and a link to the Principal Self-Efficacy Scale survey instrument. Collected data were examined using the Statistical Package for the Social Sciences software program. Investigation of the data included descriptive analyses, Pearson's correlational coefficient, and multiple regression. A significant, positive relationship was noted between mentoring support and self-efficacy for management (r = 0.19, p = 0.047); when controlling for years of experience, a significant association was noted for instructional leadership (B = 0.06, p = 0.04). The results indicate that mentoring support positively impacted the self-efficacy of principals regarding management skills, regardless of experience as a school principal. Also, experience positively impacted the self-efficacy of principals regarding instructional leadership and was not influenced by mentoring support. Results of this study provide information to district leaders making decisions about the development and funding of mentoring programs for principals. Recommended future studies include those focused on defining the mentoring process specific to principals and those seeking to clarify experiences of principals during specific phases of their careers to better understand when and how mentoring support is best utilized. [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.]