In the years since the initial discovery that blood from diabetic patients contains increased amounts of a posttranslationally gluco sylated form of hemoglobin (hemoglobin Ale)' an impressive number of studies have clarified and expanded the use of glycohemoglobin levels to assess disease status. Many other structural proteins have been shown to undergo similar changes, including proteins from tissues most commonly affected in diabetes (e.g., lens, aorta, peripheral nerve, basement membrane). Thus, the nonenzymatic glycosylation of hemoglobin emerges as an invaluable model for the pathogenesis of certain chronic diabetes complications. In addition to reviewing a wealth of investigative possibilities in the area of these chronic complications-including eye, kidney, nerve, and vascular disease-Dr. Cohen indicates how enhanced nonenzymatic glycosylation in uncontrolled diabetes underscores the pressing need for maintenance of long-term euglycemia. Dr. Cohen is an endocrinologist and diabetes specialist whose research activities have largely focused on the chemistry and metabo lism of the basement membrane in diabetes. This superb monograph on nonenzymatic glycosylation clearly shows the major trends of her past and present research and clinical activities. This book is beautifully written and a pleasure to read. It provides great insight into the mechanisms of the pathogenesis of the oom- vii viii Foreword cations of diabetes and should be of immense value not only to basic and clinical investigators, but also to internists, diabetologists, and endocrinologists in clinical practice."