This study investigated the processes and pathways of leadership development of teachers in different career stages as they participated in a professional development program. A multiple case study approach with conceptual frameworks of teacher leadership practice and identity was used. The leadership development process across all three teachers involved an alignment and synergy among their leadership views, leadership practices, and identity; however, the particular pathways of leadership development were unique for each teacher depending upon their personal priorities, school context and prior life experiences. This study contributes to the literature by documenting 'how' teachers develop as teacher leaders. (C) 2017 Elsevier Ltd. All rights reserved.