Born at Melbourne in 1886, elder son of Michael Ulick O'Sullivan LRCP&S Edinburgh, gynaecologist to the Woman's Hospital and St Vincent's Hospital. His younger brother Brendan became a physician and practised at Fitzroy, Victoria. He was educated at the University of Melbourne, qualifying in 1909, and served as a resident medical officer at Ballarat. He then travelled to Europe with his father's friend, the famous "character" Archibald Watson FRCS, professor of anatomy at Adelaide. He was in England from 1912 and took the Fellowship in June 1914. During the war of 1914-18 he worked on the staff of General Fetherstone, Director-General of Medical Services in Australia, with the rank of Captain AAMC. He was appointed to the staff of St Vincent's Hospital, where he rose to be senior gynaecologist, as his father had been. His operating theatre was frequented by surgeons from all over Australia, and a record of his surgery was filmed by Dr Frank Tate. He practised at 70 Collins Street, Melbourne. His chief recreation was travel in the remoter parts of the continent, where again Dr Tate filmed him among a tribe of aborigines. He was Dean of the Clinical School at St Vincent's Hospital in the early years of the second world war, but his health began to fail and he retired in 1946. He died at Melbourne on 10 October 1953 aged 67, survived by his wife and his brother. Dick O'Sullivan was a man of striking character, sparkling wit, and vehement speech, beloved by his patients and friends. He was a keen racing man and owned several race-horses.