The article recounts the development of a five-stage model for the professional development of school principals and school leading teams. An instrumental qualitative case study methodology was utilized, based on seven in-depth interviews with the instructors who directed professional development for school staffs. The model reflects both supporting factors and challenges to its components that derive from individual school cultures. The model facilitates planning for both structure and content of the professional development of school leadership. The article records a success in a difficult milieu.