For a variety of reasons, there has been an explosion of interest in research on aging over the past few years. The reasons include an awareness that a large and growing proportion of our popUlation is over 65 and that research findings can contribute to their health, satisfaction, and efficiency as members of society; the fact that funding agencies have endorsed the need for more research effort in the area by setting up special programs; and also the fact that researchers themselves are turning more to practical problems as many theoretical issues (in experimen tal psychology at least) seem to remain as intractable as ever. Thus, at present there is widespread interest in aging, but there is also a lack of knowledge as to what has already been accomplished in the area, what the theoretical issues are, and what factors contribute to the methodological and practical difficulties. The time is propitious for meetings of experts in various aspects of the aging process, both to discuss among themselves latest advances in the field and also to inte grate known information for researchers and practitioners. In the summer of 1980 we organized such a meeting as the 10th annual psychology symposium to be held at the Erindale Campus of the University of Toronto. The topic chosen was Aging and Cognitive Processes, and the edited contributions to the symposium form the chapters of the present book.