Gimson was educated at Emanuel School London, and University College London, where later in 1966 he became Professor of Phonetics, and in 1971 head of the Department of Phonetics and Linguistics.
He was a pupil and colleague of Daniel Jones, and is known for having updated and extended Jones's description of standard British English pronunciation (Received Pronunciation, or RP). Through his Introduction to the Pronunciation of English, first published in 1962, Gimson became an authority on Received Pronunciation. He succeeded Jones as editor of the English Pronouncing Dictionary, making significant changes to its content and presentation. He was known to generations of students and colleagues simply as 'Gim'.
Arnold, G.F. and Gimson, A.C (1965). English Pronunciation Practice. London: University of London Press
Gimson, A.C (1962). Introduction to the Pronunciation of English. London: Arnold. Fourth edition (1989) revised by Ramsaran, S.; sixth edition (2001) revised by Cruttenden, A.
Gimson, A.C (1975). A Practical Course of English Pronunciation: A Perceptual Approach. London: Arnold
^Lewis, J. Windsor (June 1976). "A. C. Gimson, A Practical Course of English Pronunciation. (Pp. viii + 80. Edward Arnold: London, 1975.)". Journal of the International Phonetic Association. 6 (1): 35-39. doi:10.1017/S0025100300001481. ISSN1475-3502.
MacMahon, M. K. C. (23 September 2004). "Gimson, Alfred Charles [Gim]". Oxford Dictionary of National Biography. doi:10.1093/ref:odnb/46942.
Wells, J. C. (1985). "Obituary: Professor A. C. Gimson". International Journal of Language & Communication Disorders. 20 (2): 117-118. doi:10.3109/13682828509012253.