Ian Maddieson (born September 1, 1942 in Watford, United Kingdom ) is British-American linguist and professor emeritus of linguistics at the University of New Mexico, in the United States. He has served as Vice-President of the International Phonetic Association, and Secretary of the Association for Laboratory Phonology. Maddieson is best known for his work in phonetics, and phonological typology. He spent most of his academic career at the University of California, Berkeley, where he often collaborated with Peter Ladefoged in describing the patterns of speech sounds in the world's spoken languages.

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