This dissertation is a qualitative study that examines expert teacher's trajectories of professional development (PD). Interviews across 39 participants produced data in the form of life-narratives revealing perceptions of growth across the teachers' careers. Using a life-narrative methodological approach (McAdams, 2011), these data were used to inform themes of beginning, transformation, and experiences of PD. Narratives were then organized based on similarities across cases. Findings include unique aspects of teacher training across cases, multiple trajectory types toward expert practice, and teacher perception of relevance for different PD experiences. [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.]