Arthur Koch was born in Colombo on 20 November 1903 into a family distinguished for public service in Ceylon. He was educated at the Royal College, Colombo, and in 1922 entered the Ceylon Medical College where he had an outstanding undergraduate career, winning 5 medals in the course of study for the qualification of LMS Ceylon which he took in 1927. After several resident appointments at the General Hospital, Colombo, he became a demonstrator in physiology in the Ceylon Medical College in 1935, being promoted to assistant lecturer in physiology and pharmacology in 1940, and lecturer in the Faculty of Medicine, University of Ceylon in 1945. In 1948 he came over to Oxford to work with Professor C G Douglas in the department of human physiology, and since he was precluded by University regulations from taking a DPhil he presented a thesis for the BSc and was granted this research degree. On returning to Ceylon he was appointed Reader, and in 1952 Professor of Physiology and Pharmacology. From 1954 till 1969 he acted as the local examiner in physiology for the Primary FRCS examinations held in Ceylon, and also for the Dental and Anaesthetic Primaries. For these services to the Royal College of Surgeons he was elected to the Fellowship in 1966. He retired from his Chair in 1968, and was made Emeritus Professor. This brief outline of his remarkable career, which omits the honours he received from various professional and scientific bodies, is yet sufficient to indicate why he was greatly respected by his colleagues in the Faculty of Medicine, and loved by his students. He was a great teacher, and his work was his life. That his reputation as a physiologist extended beyond his native land is shown by his election to the Physiological Society of Great Britain in 1957. It is also noteworthy that he was the first from the Far East to examine in the Primary at Queen Square, in the same year. He was interested in music, literature and the theatre, but his chief interest outside his work was in photography, and he received several awards at International Exhibitions held in Ceylon, and during the second world war built his own photographic enlarger. In 1941 he married Doris Christobel Mary, daughter of Dr A C A Fernando, and when he died on 7 August 1969 his wife and their son and daughter survived him.