The purpose of this phenomenological study was to explore the professional development experiences of successful secondary principals framed within the practices of the transformational leadership theory. At this stage in the research, professional development will be generally defined as all of the types of training that the administrator received to enhance leadership practices that are tailored towards their personal needs and campus goals (Hirsh, 2009). The four research questions that guided the research study examined the four qualities of a transformational leader which included intellectual stimulation, individualized consideration, inspirational motivation, and idealized influence. Ten award winning campus administrators were identified to participate in the study. Each participant was awarded Outstanding Principal of the Year within their Service Center Region of Texas. The findings indicated that the principals identified specific influences that shaped their leadership styles in each of the four categories of transformational leadership. Implications for practice include extending the research to other areas and utilizing identified influences to train administrators. [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.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]