Sidney Arthur Boyd was born at Bedford on 20 July 1880, son of Albert Thomas and Marianne Boyd. He was educated at Bedford School and received his medical training at the London Hospital and Charing Cross Hospital, qualifying in 1902. In 1904 he obtained his MB BS degree with honours in medicine, surgery, pathology and forensic medicine and was awarded the gold medal. After several resident posts at Charing Cross Hospital he took his Fellowship in 1905 and the MS in 1907. In 1912 he was appointed to the staff of the Hampstead Central Hospital and later became attached to the Victoria Hospital, Leatherhead, the Alexandra Orphanage, the LCC Hospital at New End, Hampstead, and the Mildmay Mission Hospital. During the first world war he was gazetted a temporary Major in the RAMC, serving in the Mediterranean and Egypt, and was twice mentioned in dispatches. After the war he also held the post of lecturer in applied anatomy to King's College, London, 1919-25. Owing to a rule at the Hampstead General Hospital, Boyd had to retire in 1937 after holding the post of consultant for 25 years. When the second world war came his Hospital invited him to return, and he worked there until the end of 1945. His work during the war was invaluable in helping to keep the hospital running efficiently during the emergency. Boyd lived in Hampstead all his life and took an active part in public affairs, being a member of the Hampstead Borough Council for forty years. He was Mayor of the Borough 1938-45, and in recognition of his leadership of the Council during the war years was made a Freeman of the Borough in 1946. He was also a JP for the County of London. Boyd was a man of strong Christian faith, and his association with the Mildmay Mission Hospital was especially dear to him. An active member of the British Medical Association, he was honorary secretary of the Hampstead division in 1914 and again in 1949. He was elected a Fellow of the BMA in 1960. Sidney Boyd was a brilliant abdominal surgeon; his particular forte was in the treatment of a bad appendix abscess, and in those pre-antibiotic days his mortality was very low. He was always a strong supporter of the use of the Battle incision for the treatment of appendicitis, and the complications of that incision were unknown in his hands. He married in 1910 Viola Evangeline, daughter of Henry Fox, and they had one son and three daughters. Boyd died at his home on 2 November 1966, at the age of 86; his wife survived him and died on 12 February 1968. Publications: Foreign bodies in the vermiform appendix. *Brit med J* 1912, 1, 828. Non-parasitic cysts of the liver. Lancet, 1913, 1, 951.