John Graham Pyper, the eldest of three sons of John Pyper MA, a schoolmaster, and of Bessie Pyper (née Patton), was born at Bangor, County Down, on 26 June 1912. His second brother became a consultant physician and the youngest an orthopaedic surgeon. After education at Bangor Grammar School, where he was an exhibitioner, and at Queen's University, Belfast, he graduated in 1935. At university he had a distinguished sporting record, receiving a blue for swimming and a half blue for athletics, and winning gold medals for diving in several university championships. He also represented the British universities at the world student games in Turin in 1933. After resident appointments at the Royal Victoria Hospital, Belfast, where he obtained a gold medal for his MD in 1938, he was a demonstrator in physiology at Queen's, before working at the Radcliffe Infirmary, Oxford. From November 1939 to December 1945 he served in the RAMC as a general duty officer, and as a blood transfusion officer in Malta where he was mentioned in despatches in 1942. He was then a graded surgeon in the Middle East Forces before demobilisation with the rank of Captain. He returned to the Royal Victoria Hospital as a surgical registrar and worked with Robert McConnell, James Loughridge and Sir Ian Fraser, but he also recorded his indebtedness to Russell Howard of the London Hospital. After appointment as consultant surgeon to the old City and County Hospital, and at Waterside Hospital in Londonderry, he carried an enormous workload of general and traumatic surgery almost unaided. He served as honorary secretary to the planning committee for Altnagelvin Hospital which was the first completely new hospital to be built in the UK after the war. Despite several major heart attacks he continued to work there as senior surgeon until 1973 and was later appointed as a life governor. He was also a founder member and chairman of the Londonderry Swimming Club; president of Rotary 1970-71; a trustee of Magee University until 1973, and chairman of the building committee and a member of the court of the New University of Ulster until 1973. In 1956 he had been appointed honorary surgeon to the Royal Navy in Northern Ireland, and as a magistrate in 1971. He was remarkable for his unstinting service, his skill, and the enormous amount of time which he devoted to care of the sick. He retired from the National Health Service, mainly on health grounds, in 1973, to become senior medical officer and surgeon to Ascension Island, serving there until 1977 when he retired to Framlingham in Suffolk. In later years he included photography and hill walking amongst his hobbies. During the war he met and married Patricia Brightman when she was serving in the Transport Corps, and they had three sons and a daughter. When he died on 15 May 1987 he was survived by his wife, children and seven grandchildren.