This book, written for managers, specialists, and students of management, is based largely on the author's experience in helping organization leaders with planned-change efforts, and on related experience of colleagues in the field. Chapter 1 presents the background and causes for the increased concern with organization development and planned change. Chapter 2 defines organization development, training, and operations research. Chapter 3 reviews and describes the types of strategies, tactics, and activities that are used in organization development efforts. The next five chapters are case studies of organizationwide, planned-change efforts. Each case represents a specific change-target emphasis -- a change in the "culture" of the organization; in managerial strategy; and in the way work is organized; creative adaptation to a new environment; and changes in influence and communication patterns. Chapter 9 analyzes the conditions and characteristics of successful and unsuccessful organization development efforts. Chapter 10 is concerned with different strategies of managing. The last chapter looks briefly ahead to what we might expect as major influences in the field of organization improvement in the next decade. (Author/NL)