This booklet attempts to give a brief overview of the nature of organization development (OD). It describes the role of the professional organization development specialist, how he functions, and what he tries to do in the client system. It also describes the purposes of the Midwest Organization Development Network, a nonprofit association of OD professionals. Seven major assumptions about organizations are proposed, and a 12-step process for beginning OD programs in client systems is outlined. The booklet concludes with a review of the kinds of learning outcomes organizations may expect from OD programs. (Author)