Alfred Geddes Tresidder was born on 15 December 1881 and was educated at Falmouth Grammar School and the London Hospital, where he qualified with the Conjoint Diploma in 1906, and graduated MB BS London in 1907. He then worked for a time in general practice and entered the Indian Medical Service in 1908. In 1911 while on leave from India he passed the MD examination in obstetrics and gynaecology. During the first world war Tresidder served in Mesopotamia and was mentioned in dispatches. When the war was over he returned to the London Hospital as house surgeon in the ear, nose and throat department, and subsequently otolarynology became his special interest. Returning to India he was attached to the Bombay Presidency as a civil surgeon, and for some years was on the personal staff of Sir Leslie Wilson, Governor of Bombay. In 1927 he was appointed CIE, and in 1931 he obtained leave to study in Vienna and then took the MS London in otolaryngology. In 1932 he decided to retire from the IMS and returned to London where in addition to general practice he was appointed to the staff of Blackheath and Charlton Hospital. During the second world war he joined the RAMC and worked as an ENT specialist at Woolwich, Netley, and Bath. In 1947 he became consultant ENT surgeon to St Helier Hospital, Carshalton, retiring in 1957. In 1946 Tresidder joined his son Gerald who was working for the Fellowship, and they both passed the Primary and Final examinations. Tresidder married Lilian Annie Trelease in 1909 and they had two daughters and one son who became urological surgeon to the London Hospital. He died peacefully in hospital on 9 July 1970, aged 88.