Born on 9 June 1887 at Ely Place, Dublin, son of Walter Doolin, an architect, he was educated first by the Marist Fathers, and later by the Jesuits at Clongowes Wood College. He matriculated in the Royal University of Ireland 1904 and had a distinguished undergraduate career at University College, Dublin, being in 1910 the first honours graduate to sign the role of the newly instituted National University of Ireland. Thereafter he carried out postgraduate study in anatomy and surgery in France, Germany and Britain. His wonderful facility in languages enabled him to derive enormous benefit from his postgraduate studies and later assisted him as a medical historian. He took the Irish FRCS in 1912, and finally returned to Dublin in 1914, where he was appointed surgeon to St Vincent's Hospital and later to Temple Street Children's Hospital. Doolin had a flair for teaching and wrote extensively, in particular on abdominal surgery and on cleft palate. He was, however, extremely modest and self critical. He became editor of the *Irish Journal of Medicine* in 1925 and of the *Journal of the Irish Medical Association* in 1954, in which year he became honorary Professor of the History of Medicine at University College, Dublin. He was Vicary Lecturer of the Royal College of Surgeons in 1950 and Litchfield Lecturer in Oxford, and lecturer to the Academy of Surgery in Paris. President of the Royal Academy of Medicine in Ireland in 1938, he became a member of the General Medical Council in 1954. He was on two occasions president of the Leinster Branch of the BMA, and vice-president of the section of surgery in 1929 and in 1933. He became an honorary Fellow of the French Academy of Surgery in 1958. In his younger days he was a keen athlete, particularly as a swimmer and cricketer, and as a tennis player of experience he umpired the Davis Cup matches in Dublin. He married twice: leaving two sons and three daughters of his first marriage, and was survived by his widow and their two sons. Doolin died on 16 April 1962 aged 74.