Morrison-Scott was appointed as an Assistant Keeper (2nd class) in Department of Zoology at the British Museum (Natural History) on 1 October 1936.[2] During World War II, he was a member of the Royal Naval Volunteer Reserve and commanded a flotilla of tank landing craft during D-Day in Normandy, earning the Distinguished Service Cross (DCS).[3] He was promoted to Assistant Keeper (1st class) in 1943. He became the Head of the Mammal Section in 1945 and Principal Scientific Officer in 1948. From 1956–1960, he was Director of the Science Museum.[4] Then from 1960 he was Director of the British Museum (Natural History) until his retirement on 30 November 1968.[2]
A list of British mammals [by] T.C.S. Morrison-Scott Published London, Printed by order of the trustees of the British Museum, 1952.
Southern African mammals, 1758–1951: a reclassification, by J. R. Ellerman, T. C. S. Morrison-Scott, and R. W. Hayman, 1909–1973 Published London: Printed by order of the trustees of the British Museum, 1953.