Dermot O'Flynn was a consultant surgeon in the urology department at the Meath Hospital and County Dublin Infirmary, Dublin. He was born on 21 January 1920 and studied medicine at Cork, qualifying in 1942. After house jobs in Mansfield and Lincoln, he joined the RAMC, which took him to West Africa as a graded surgeon. He rose to the rank of captain and for a short time commanded No 52 Hospital in Kumasi. In Accra his commanding officer was the orthopaedic surgeon Herbert Edward 'Ding' Harding, and at the end of the war he joined Harding at St Stephen's Hospital, Fulham, as a casualty officer while studying for the fellowship. He gained the fellowship of the Royal College of Surgeons of Edinburgh in 1948 and in the same year became a registrar to David Band and Selby Tulloch in Edinburgh, two of the founding fathers of the British Association of Urological Surgeons. In 1952 he took the MCh in Edinburgh and in the same year was appointed as an assistant surgeon to the Meath Hospital in Dublin. In those days the Meath was renowned for transurethral prostatectomy thanks to the efforts of Tom Lane, who had gone over to the Mayo Clinic to learn the cold punch technique. When O'Flynn won the Ainsworth scholarship, Lane sent him to the Mayo Clinic to study the latest advances in the cold punch method. It was some time after his return to the Meath, and some 500 cold punch operations later, that a visitor came from Albany, New York, to give a demonstration of the hot wire resectoscope method. It was an instant conversion. In collaboration with his colleague, Victor Lane, O'Flynn made the Meath the centre of hot wire resection. Soon they showed that this new method could reduce mortality by a factor of ten. This was the first in a long list of innovations from the Meath, all based on the punch-card record system which O'Flynn had introduced. Thanks to this punch-card database, the Meath team produced one major contribution after another, covering subjects as diverse as testicular tumours, tuberculosis calculi, neuropathic bladder and bladder cancer. He was a visiting professor in the US, Australia and the Gulf. He became a fellow of the Royal College of Surgeons in Ireland *ad eundem* in 1968, and went on to serve as president from 1992 to 1994. In 1993 he was made an honorary fellow of the Royal College of Surgeons. He was also a long-standing member of the British Association of Urological Surgeons. In his spare time O'Flynn played golf and was a competitive sailor. He was at one time captain of the Dublin Bay Dragon Fleet, which follows a 900-year tradition of sailing dragon ships off the coast of Ireland. He was also a skilful and sensitive water-colour painter. O'Flynn died on 16 January 2014 at the age of 93. Predeceased by his wife Monica (née Kelleher), he was survived by his children, Desmond, Kieran, Dermot, Denise and Brian, and 16 grandchildren.