Born in Oudtshoorn, Cape Province, South Africa, on 26 May 1900, the only son of Elias Meyer Sacks, a tobacco manufacturer, and Rachel Berman whose father was an exporter of ostrich feathers, Isak George Sacks was educated in the Boys' High School, Oudtshoorn, the Marist Brothers' College, Uitenhage, and the University of Cape Town before entering Trinity College, Dublin to read medicine in 1919. He qualified in 1922 and after resident appointments in Swansea he returned to Cape Town in 1927 as a surgeon, joining the staff of Groote Schuur Hospital where he became a consultant surgeon and later senior surgeon, during which time he was responsible for training and placing a generation of surgeons. He was compassionate and skillful as a surgeon and, in spite of occasional outbursts such as throwing 'blunt' scalpels across the operating theatre, inspired great affection in his staff. In 1937 with Betty Radford (whom he had married in 1935) he founded *The Guardian*, a weekly journal dedicated to fighting against racial injustice. He stood as a Communist party candidate in 1943 against the sitting member, the Minister of Justice, who was a friend of his in private life. The election was a 'most gentlemanly affair'. The Communist candidate, full of apprehension at the possibility of election by the voters, wandered off with his dogs for long walks on the beach, leaving his enormous band of helpers convinced he was busily canvassing. He lost his deposit. He wrote *The intelligent man's guide to Jew-baiting* in 1934 and it was published by Gollancz. Later, at the request of Harold Laski, John Strachey and Gollancz he wrote a shorter but similarly oriented booklet for the Left Book Club People's Library *The Jewish question*. He edited a quarterly journal *The Critic*, contributed a weekly political column for his wife's journal and wrote many pamphlets. He became disenchanted with Communism and, in 1946 was expelled by the party. He threw himself into building up the Groote Schuur Hospital and began to travel widely, building up contacts in Europe and the United States which enabled him to be of great help to his registrars and housemen in finding postgraduate appointments. His political past made him a constant target for harrying by the South African Government and, shortly after Sharpeville, in 1961, George and Betty decided to move to London. He was too old to restart his career as a surgeon but put his literary talents to good use by becoming assistant editor of the Lancet from 1962 to 1967. He died on 8 December 1981, aged 81 years. His wife predeceased him by eight years and they did not have any children.