This monograph guides administrators in developing policies that lead to improved supervision of instruction. Chapter 1, "The Mystery of Effective Teaching," by Barbara Benham Tye, focuses on improving schools' work environment through the supportive methods of clinical supervision. Arthur L. Costa describes five phases of the process between supervisor and teacher in the second chapter, "Clinical Supervision--A Definition.""Reviewing the Difference between Supervision and Evaluation," chapter 3, by Arthur L. Costa and Robert Garmston, distinguishes nine processes in which supervision and evaluation are performed differently. Chapter 4, also by Costa and Garmston, discusses assumptions and goals in "Cognitive Coaching--Supervision for Intelligent Teaching." Michelle Williams relates personal experiences in chapter 5, "Peer Coaching Improved My Teaching," by describing advantages of the model. "The Role of the Principal as Instructional Leader," by Kenneth A. Tye, chapter 6, surveys demands placed upon principals and recommends new types of training programs. The final chapter, "The Role of the School Board: Linking the Professional and Political Worlds of Clinical Supervision," by Richard C. Williams, recommends that teacher supervision involve teachers in procedures; as political bodies, boards must acquaint themselves with teaching procedures as well. A bibliography provides 25 references. (CJH)