School principals' education and professional experience shape their approach to school leadership and how successful their students will be. However, it is not clear from existing research which aspects of principal education and professional experience are related to student outcomes and principal retention. This dissertation explores aspects of a potential principal's education and professional experience that states and school districts should look for and cultivate in candidates for the position of school principal. The work was guided by two research questions: 1) how are principals' education and professional experience related to student outcomes and principal retention? and 2) how can state certification and district hiring policies better incorporate information about a principal's education and professional experience to improve principal effectiveness? Using information on principals trained by the New Leaders program and school-level data from four large urban districts, I analyzed the relationships between principal education and professional experience and student outcomes and principal retention. I examined state certification and district hiring policies for the four urban districts used in the analysis and conducted a survey of 33 districts regarding their hiring policies and practices. From this research, I provide recommendations designed to inform state certification policy, district hiring policy, and training program curricula. The following are appended: (1) Principal Hiring Survey; (2) Coding Rules and Variable Description; and (3) Additional Results. [This dissertation was supported by the Susan Way-Smith Dissertation Grant in Education.]