This textbook, designed to be used in teacher preparation courses focuses on observation of students and the role it plays in instructional decision making. The first chapter discusses the necessity of observation of students in the learning environment. Chapter two identifies the general principles, procedures, and problems applicable to all observation situations. Chapters three, four, and five deal with specific types of records used for observation: behavior tallying and charting, checklists, rating scales and participation charts, and anecdotal records. The last chapter discusses observation of instructional environments and teacher behavior. Each chapter in the book is followed by suggested activities which are designed to reinforce the concepts taught in the chapter and to provide practice in implementing the techniques described in the chapter. (HMD)