Organizational Behavior often influences many modem management decisions, Managers and other human resource professionals are presented with analyses, proposals, etc. to help them improve their organizations. How can they judge the validity, accuracy and efficiency of these proposals? Perhaps one way they can evaluate them more accurately is to understand something of how the field of organizational behavior developed and the backgro1md of some of its major thinkers. This increased understanding might be heightened by knowing how the major contributors feel about their contributions and the sources of their seminal ideas. This discussion of the origins and development of the field of organizational behavior provides the background and understanding which can increase the accuracy with which today's managers and professionals judge the quality of the large mass of organizational bdu.V1or based information which they receive. Such increased accuracy may be of vital importance to the success of their organizations and of their own careers. Because organizational behavior is such a young field with many of its earliest contributors continuing to do research, the strategy adopted for summarizing it was telephone interviews with about seventy of the leading experts in the field. The interviews were conducted by the authors of this paper. This data base was supplemented by an analysis of written documents about the field's development, and the development of a time line of important events based on scrutiny of Academy of Management activities over the years and on the environment as a whole (for example, the Gordon and Howell report, 1959). The distillation of effort reported here is divided into six subsections and an appendix on methodology: origins and evolution of organizational behavior, definition of the field and its distinction from other fields, major influences on the way our respondents view the field, major themes that have emerged, major contributions of the field, and outsiders' perceptions of organizational behavior.