The composition of the American workforce is quickly shifting, with Millennials assuming leadership positions early in their careers due to Baby Boomer generation retirements and the relatively small Generation-X population. Using an exploratory narrative case study design, I empirically documented the leader identity development of seven Millennial staff administrators at three different four-year universities in the southern region of the United States. I also identified how Millennial leaders defined effective leadership and explored how the characteristics attributed to Millennials may be influencing their development as leaders. I found the participants shared memories that they considered significant occurred during their adolescence, a critical time for their Millennial identity development. Additionally, my results indicate that my participating Millennials defined effective leadership in relational attributes and valued mentoring. Finally, my data showed that qualities stereotypically attributed to Millennials likely influenced and will continue to influence their leader identity development and their professional path toward achieving, seeking purpose, and pursuing organizational leadership roles. Findings from my qualitative study provided insight into the intersection of leader identity development and Millennial identity. My research has implications for leadership research, leader professional development, leadership support, and generational differences in leadership. [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.]