This handbook is written for teachers in leadership roles, including team leaders, lead teachers, department chairpersons, and master teachers. Part 1, "The Nature of School Leadership," is devoted to a description of teacher leaders and how they lead. Results are provided from research on teacher leaders, and persistent obstacles to establishing more effective teacher leadership are identified. Keys to establishing helping relationships with colleagues are discussed, and suggestions are given for teacher leaders seeking to improve upon instructional programs while effectively evaluating their efforts. Part 2, "The Instructional Process," focuses on the information teacher leaders need in order to work with peers to improve instruction in individual classrooms. Chapters are provided on planning, presenting, and evaluating instruction from the teacher leader's perspective. Part 3, "Teachers Working Together To Reclaim Schools," focuses on what teacher leaders can do to implement and support professional development programs in their schools. Guidelines for establishing peer coaching programs are provided, as well as a discussion on long-term restructuring and renewal in the face of previously identified barriers to change. (Contains 190 references.) (PB)