The purpose of this study was to determine the factors that impacted the level of self-perceived transformational leadership potential in pre-service school library media specialists who participated in a master's degree program in library and information studies focusing on leadership development. The participants of the study were a cohort of 30 teacher-leaders from 6 counties within the state of Florida. A mixed-methods concurrent triangulation research design was implemented by using pre-existing data, the Leadership Practices Inventory (LPI), and a survey designed by the researcher. The qualitative data were coded into themes, while the quantitative data were analyzed using four statistical methods: Chi-square test, T-test, Spearman correlation coefficient, and the Pearson correlation coefficient. The findings indicated that the participants' leadership training facilitated the development of their self-perceived transformational leadership behaviors to a significantly higher level than the established national norms for the LPI in two areas--Modeling the Way and Enabling Others to Act. In addition, the assessment of leadership potential given during the program selection process had a positive correlation with the LPI subscale for Enabling Others to Act. Moreover, the social context of each participant's circumstances had an impact on their self-perceived transformational leadership potential when considering the participants' satisfaction with the support they received from their mentors, the amount of time they spent with their mentors, whether they selected or were assigned a mentor, their Graduate Record Exam scores, and the poverty level within their schools. [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://www.proquest.com/en-US/products/dissertations/individuals.shtml.]