William Dawson MacDonald was born in Kitchener, Ontario, Canada, on 27 April 1931, the elder of two sons of William Grant MacDonald, a doctor of medicine, and Edith Christie MacDonald née Dawson. He was educated at Victoria Public School, and then the Kitchener-Waterloo Collegiate Institute and the University of Western Ontario. He held posts at the Royal Victoria Hospital, London, Ontario, and the Hospital for Sick Children in Toronto. He then went to the UK, first to Warwick Hospital and then to the Radcliffe Infirmary, Oxford. In Warwickshire he was influenced by G R Taylor, C R Savage and J D Marsh. He gained his FRCS in 1966. Outside medicine, he enjoyed hunting and skiing. In 1959 he married Jennifer Radford, who also qualified MB BS, and they had three daughters. He died on 10 March 2011, at the age of 79.