This volume describes the principal ideas and developments in endocrinology, from the time of Aristotle to the most recent discoveries. It begins by discussing vasopressin, and then examines the development of concepts in the control of pituitary hormones and their target glands. Also covered are the various pituitary hormones under neuronal control, pituitary target glands, peripheral hormones, pancreatic hormones, hormone receptors, and comparative endocrinology.