Professor of Linguistics at the University of Michigan-Dearborn. He studied linguistics and Celtic languages at Harvard and Oxford universities, and taught linguistics for eight years at the University of Hong Kong. He has published papers on a range of topics including Celtic linguistics, dialectology, American English, descriptive grammar, and the linguistics of trademark law and mathematical notation. He is Co-Editor (with Kingsley Bolton) of the journal World Englishes (Wiley), and is Executive Director of the International Association for World Englishes (IAWE).