This book is written for practicing and prospective instructional leaders who want to develop reflective, collaborative, problem-solving contexts for dialogue about instruction. Some school leaders, though, have discovered ways to effectively integrate such leadership into their schools, and these methods are presented. This book draws on information from a study of more than 800 K-12 classroom teachers who were asked how the best principals encourage teacher growth and professionalism. Teachers described in detail the strategies, behaviors, attitudes, and goals of instructional supervisors that influenced classroom instruction. The book opens with an overview of the literature on instructional leadership and supervision, as well as a brief description of the study on which it is based. Chapters 2, 3, and 4 focus, respectively, on three fundamental themes of instructional leadership: talking with teachers, promoting teachers' professional growth, and fostering teacher reflection. Chapters 5, 6, and 7 discuss principles' use of visibility, praise, and autonomy--as juxtaposed with abandonment, criticism, and control--and their affects on teachers. Chapter 8 summarizes the findings and presents a portrait of good instructional leadership. (Contains an index and approximately 225 references.) (RJM)