School organizations can benefit from improvement planning that emphasizes cross-functional, team experiences, where practitioners both learn and lead together. The Distributed Leadership (DL) Program offers an extensive team-leadership design framework for guiding systemic improvement planning in schools, plus a perspective on leadership development that is strengthened by the following observation: the practice of twenty-first-century organizational leadership requires attention to, and an ability to design for, cross-functional, professional leadership teams. To this end, the DL Program incubated heterogeneous leadership teams, and crafted an instructional curriculum for their professional learning and development, as well as the promotion of leadership capacity in schools. The lessons learned in the DL Program may inform strategic efforts to grow team leadership in school organizations. DL teams use learning as a lever for leadership development. The learning entails a leadership curriculum and makes use of teachers' energies in guiding action plan codevelopment and implementation.