Collective School Leaders are school administrators who embody collective leadership to equip and empower school stakeholders, particularly teacher-leaders. Collective School Leaders effectively harness the collective power of stakeholders to build and sustain multifaceted leadership that drives student outcomes. This narrative case study analyzes the working group discussions and semi-structured interview responses of Teach Plus participants. As a workplace initiative, Education Leadership Coaches and Teach Plus Teacher-Leader Fellows selected five essential competencies of collective school leadership: personal awareness, collaborative vision-setting, distributed leadership, systems innovation, and equity advocacy. Participants in this Teach Plus case study recommend that school leaders who exhibit the five competencies of collective school leadership are poised to promote and expand teacher-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.]