Raymond Urgel Lemieux, CC, AOE, FRS (June 16, 1920 – July 22, 2000) was a Canadian organic chemist, who pioneered many discoveries in the field of chemistry, his first and most famous being the synthesis of sucrose. His contributions include the discovery of the anomeric effect and the development of general methodologies for the synthesis of saccharides still employed in the area of carbohydrate chemistry. He was a fellow of the Royal Society of Canada and the Royal Society (England), and a recipient of the prestigious Albert Einstein World Award of Science and Wolf Prize in Chemistry.