Isidor Schwaner Ravdin was born in Evansville, Indiana, on 10 October 1894, his father and grandfather having been doctors. In 1916 he graduated in science at the University of Indiana, and in 1918 in medicine at the University of Pennsylvania. After holding junior surgical posts in Philadelphia, in 1927 he came to Edinburgh and spent a year with Sir David Wilkie. He also worked in the physiological laboratory and so laid the foundation of his subsequent researches into physiological and biochemical problems applied to surgery. On his return in 1928 he was made Professor of Surgical Research, and in 1935 Harrison Professor of Surgery. He thus undertook a fantastic programme of clinical and laboratory work, his chief contribution being the introduction of intravenous feeding to overcome malnutrition in surgical patients. He also stimulated by his example and advice a large number of assistants who subsequently distinguished themselves as a result. In the second world war he served in the Eastern theatre and ultimately became the first Major-General in the Medical Corps Army Reserve: After the war he was appointed John Rhea Barton Professor and Chairman of the Department of Surgery in Philadelphia, retiring in 1959 because he wanted to make way for a younger man, and he became Vice-President for Medical Affairs. Ravdin was awarded many honours including the Presidency of the American Surgical Association in 1958 of the American Cancer Society in 1963, and of the American College of Surgeons in 1960, having been Chairman of its Board of Regents from 1954 to 60. In 1956 he was awarded the Honorary Fellowship of the Royal College of Surgeons of England. In 1921 he married Betty Glenn who was also a physician, and she was a wonderful support to him in the rest of his strenuous career. Unfortunately in the end he suffered from a chronic illness which incapacitated him mentally and physically and his death on 27 August 1972 came as a merciful release.