The 1983 publication of "A Nation at Risk" gave birth to an effort to reform K-12 schools and increase student achievement all over the United States. More than 30 years later, the school reform efforts have grown into immense industries with marginal effect. Major legislation and programs have been launched throughout 3 decades, with "No Child Left Behind" legislation and "Common Core States Standards Initiative" being the latest and biggest endeavors, still with minimal outcomes. These efforts follow and run along with many years of structural changes such as Voucher, Small, Pilot, and Charter Schools. The problem of effectively transforming K-12 schools into places of high student achievement remains intractable. The principal's role by its unique position in the educational delivery structure and its very nature is key, and may be the single most determining factor in the failure or success of a school. There are very few studies that focus on principal leadership and its effect on student achievement outcomes. All studies and most literature on principal leadership and effectiveness put most attention on traits and observable behaviors. However, it is important to look at the inner world of principals, for this influences, if not determines, the traits and behaviors they exhibit in their leadership. There are no known studies that have focused in on the inner states and experiences of effective school principals. This phenomenological study represents a seminal effort to study the inner experiences of principals. The participant selection was done through criterion type purposive sampling to link this study to leadership effectiveness. Only principals who were able to transform their schools from failing into successful according to the objective California State Standards of Adequate Yearly Progress were included. This sampling method also enabled the study to look deeply into the inner phenomenological experience of these transformative principals. The study findings yielded data compelling enough to propose a conclusion of effective school transformation and proposed a model to illustrate how the inner experiences of principals fit into effective school transformation. The study also presented its implications, limitations, and recommendations for future research. [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.]