This study applied situational leadership and transformational leadership theories to discern essential elements of principal preparation program field experiences and internships that contributed mostto principal effectiveness. Identifying critical components of principal preparation field experiences and internships were imperative to ensure principal effectiveness within the ever-changing landscape of education. The objective of this study was to discover essential components of field experiences and internships provided by principal preparation programs that contributed most to principal effectiveness, increasing the likelihood public school districts hired principal candidates who were equipped with the skills necessary to step into the position with minimal on-the-job training. A total of 23 novice principals across three target states comprised the full sample. Whereas 3 participants from the full sample, one per target state, constituted the subgroup. The mixed methods study comprises two parts: a quantitative survey followed by qualitative interviews and observations of a subgroup. The quantitative survey data were analyzed using Qualtrics frequency distribution and descriptive statistics reports. Additionally, the qualitative interview data were analyzed utilizing open coding and observation data via sorting. Lastly, a cross-case analysis of the collective case study data was employed. The highest ranked essential element per domain included using data to inform instruction; developing a safe school environment; developing relationships with students; working with the local community; and managing school schedules. In conclusion, by providing a roadmap of such essential elements of principal preparation fieldwork, principal preparation programs will be more likely to design and implement domain-specific contextualized experiences that produce principal candidates who are equipped with the skills necessary to step into the campus leadership position with minimal on-the-job training. [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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]