Karl G. Hofbauer holds the Chair for Applied Pharmacology at the Medical Faculty of the University of Basel. He received his M.D. degree from the University of Vienna, Austria, and specialized in experimental pharmacology at the University of Heidelberg, Germany He spent more than 20 years in preclinical research at Ciba, later Novartis, in Basel, Switzerland, where he became interested in the search for antiobesity drugs. He has continued to work on this subject after moving back to academia. Ulrich Keller received his training in endocrinology and internal medicine in Zurich; Basel; Nashville, Tennessee; and Rochester, Minnesota. He is currently head of the division of endocrinology, diabetes, and clinical nutrition; since 1988, he has held the position of professor of medicine at the University of Basel. His main clinical activities are diabetology (type 1 and type 2 diabetes) and obesity and lipid disorders. This can only be achieved in close collaboration with other services of the hospital (diabetes and nutrition counseling; nephrology; gynecology; ophthalmology; cardiology; and others). Interdisciplinary consultations are specifically devoted to the assessment of morbidly obese subjects. Olivier Boss received his training in medical biochemistry, exercise physiology, and endocrinology of energy metabolism from the University of Geneva (Switzerland) and Harvard Medical School and Beth Israel Deaconess Medical Center (Boston, Massachusetts).