The purpose of this study is to explore how the interactional processes between young professionals and their coach develops leader-identity over time. The explosive growth of coaching as the dominate leadership development practice continues to outpace scholars efforts to understand how it works (Pandolfi, 2020). Dominant psychotherapy approaches (Gray, 2006; Cox et al., 2014) in coaching research and practice have ignored what occurs within the "waterline" (Fillery-Travis & Cox, 2018, p.527): the meaning-making social interactions between the client and their coach. Through an integrative theoretical lens of symbolic interactionism, transformative learning, and leader-identity development, this study found seven general social interactions in coaching: (1) "asking questions," (2) "responding," (3) "highlighting," (4) "affirming," (5) "sharing insight," (6) "challenging," and (7) "stating action." Using the methods from program evaluation and narrative inquiry, an original leader-identity transformation framework was constructed to analyze and tell the stories of how coaching interactions between eleven young professional clients and their coaches transformed the way they saw themselves as leaders. The findings of this distinctive study excavate our understanding of coaching processes and leader-identity transformation, providing greater direction and valuable insights for researchers and practitioners to help young professionals navigate the demands of 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://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]