From the beginning, the systems research movement has shown a high potential for offering a conceptual framework for the understanding of social systems. Much of this potential has been realized, but a major gap remains with regard to operational investigative aids. Developments of the last ten years with a method ological orientation and emphasis seem finally to be filling this gap. The purpose of this book is to describe the most advanced of these developments and to make them available to a wider audience. The emphasis is on developments that are primarily oriented toward interaction with expertise in the social sciences and that thus hold the most promise for social systems investigation. In particu lar, attempts have been made to provide substantiation and illustration of three main points: (1) the common motivation and essential integrability that systems research provides for developments and considerations along a very broad spec trum of interests; (2) the very diverse nature of the types and forms of considera tions that may be meaningfully integrated; and (3) the operational and usable nature that developments in systems methodology represent for research in the social sciences. The book is divided into three parts with a generally increasing degree of specificity. The first part (Chapters 1, 2, and 3) deals with foundational issues associated with modeling and methodology as areas worthy of study in their ix X PREFACE own right.