Donald Barlow was born on 4 July 1905 in Leytonstone, son of Leonard Barlow, an electrical engineer, and Katherine Monteagle. His eldest brother Leonard was killed at the age of 18 after winning the MC with two bars in the Royal Flying Corps; the second became FRS and a professor at University College, London; the youngest became a successful engineer. Donald Barlow was educated at Whitgift School, Croydon, and University College and Medical School, London, where he qualified in 1927, having been much influenced by Wilfred Trotter and Gwynne Williams. He passed the FRCS at the age of 24 but had to wait until the next year before he could receive the diploma, being thought too young for the distinction. He also won the gold medal for the MS. He took a series of junior posts at the Norfolk and Norwich and the West London Hospitals, where Tyrrell Gray and Oswald Anderson directed his attention to the surgery of the chest. In 1934 he married Violet Elizabeth McIver, a theatre sister at Great Ormond Street Hospital. He was appointed consultant surgeon to the Southend Hospitals in 1936; to St John's Lewisham in 1937 and to Luton and Dunstable in 1940. Motoring was easier in those days and he combined these dispersed appointments with a thriving practice in Harley Street. He remained in these posts under the Emergency Medical Service throughout the war, but then gave up Lewisham for the London Chest Hospital, where he built up a reputation as a thoracic surgeon. Barlow served the College as an Examiner and Penrose May Tutor. He made important contributions to the literature of surgery, including chapters in Rodney Smith's *Progress of clinical surgery* (1960) and Rob and Smith's *Operative surgery* (1969). Important innovations in surgery included his revolutionary bilateral adrenalectomy and oöphorectomy: the operation was first performed on two terminally ill patients with breast cancer, both of whom recovered to enjoy another twenty years of life. He also devised several ingenious instruments, including a vascular clamp and a gastroscope. A frequent visitor to Ceylon, where he was able to teach the surgical treatment of tuberculosis, he accepted an honorary MB BS (Ceylon) but declined the offer of a CBE. India, Egypt and Iraq were among other countries which he helped with advice given at the highest level on the treatment of TB and on the development of skills in cardiac and thoracic surgery. Barlow's retirement in 1970 gave him the opportunity to enjoy his many hobbies, including painting in watercolours, writing and playing golf. He died on 5 July 1994, survived by his wife, a son, John, also FRCS, and three of his four daughters - Mary (qualified in law), Diane (BA, a linguist and artist) and Jane (a nurse). His daughter Jennifer had died while she was a law student.