It was our privilege, some twenty years ago, to assemble a group of Canadian and American investigators to examine the status of research in the then newly burgeoning field of psychological stress (Appley & Trumbull, 1967). As noted, in Chapter 1 of the present volume, there has been rapid development of the area since then. The conference on which the current volume is based was designed to do three things: 1. to further update the field, 2. to bring European and other perspectives to the subject, and 3. to focus on the status of theory of stress. We believe the reader will agree that all three objectives were accom- plished, though in so vast and active a field, one can never be totally satisfied. The authors included in this volume are among the leading inves- tigators in the field. They represent active research centers and programs in Austria, East and West Germany, Great Britain, Israel, Sweden, and the United States. Their chapters make contributions to stress theory and methodology, inform us meaningfully of the perspectives of the various research programs they represent, and provide, collectively, a description of the dynamics of the stress process as currently emerging.