The purpose of this research was to explore and describe the development, implementation, and impact of the Dallas Independent School District's (ISD) Aspiring Principals Program. This study of principal preparation has relevance as a K-16 issue for two primary reasons. First, K-12 schools are focused on graduating students who are college and career ready and strong principal leadership is an essential component in achieving this post-secondary success. Second, most school leaders are prepared--and certainly certified--through a university program so a discussion of best practices in principal preparation is pertinent as a K-16 issue. Following the review of literature which examined the changing role of the principal from colonial to contemporary times, the impact of school leadership on student achievement and best practices in principal preparation, the research methodology was discussed. A qualitative methodology was used in order to richly describe the case of the Aspiring Principals Program. The case study facilitated a deep understanding of the development, implementation, and impact of the Aspiring Principals Program through an examination and analysis of archival documents and interviews. Interviews were conducted with 13 Dallas ISD leaders at different levels in the organization--senior executive, principal, and teacher--who were involved with the development, implementation, and/or the impact of the Aspiring Principals Program. Because of the emphasis on equity as a key component in school effectiveness, the theoretical framework was critical theory. Findings were reported regarding the purpose and process for developing the Aspiring Principals Program, the description of the philosophy and components of the program, as well as the impact of the program. Program impact was addressed through an analysis at multiple levels from participant attitude to organizational support and student achievement. Since critical theory was the theoretical framework, the impact of the equity focus of the program was assessed. Recommendations regarding the program, with a focus on impact and sustainability, were made as were suggestions for further research, including analyzing program impacts on student achievement and examining models for sustainability. [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.]