The islets of Langerhans, the primary source of hormone production in the pancreas, have been the focus of research into the nature of diabetes for decades. In recent years, the molecular biology of this multiendocrine organ has been intensively investigated, with a corresponding increase in our understanding of the normal and pathological functioning of islet cells. Molecular biology of the islets of Langerhans provides the first comprehensive treatment of molecular studies on the synthesis of insulin, glucagon, somatostatin and pancreatic polypeptide. In addition, this volume presents contemporary hypotheses and explanations, at the molecular level, of the defects in islet cells that may lead to diabetes. The material presented here will be essential reading for researchers in human endocrinology and, in particular, for those working in the area of diabetes research.