I would not be among you to-night (being awarded the 1964 Nobel Prize in Physiology or Medicine) but for the mentors, colleagues and students who have guided and aided me throughout my scientific life. I wish I could name them all and tell you their contributions. More, however, than anyone else it was the late Rudolf Schoenheimer, a brilliant scholar and a man of infectious enthusiasm, who introduced me to the wonders of Biochemistry. Ever since, I have been happy to have chosen science as my career, and, to borrow a phrase of Jacques Barzun, have felt that 'Science is, in the best and strictest sense, glorious entertainment'.