His research interests include English language and literature worldwide, language and globalisation, multilingualism, sociolinguistics, and world Englishes. Much of his research has been on language issues in the Asian region, and he has published widely on English in Hong Kong and mainland China. He is the founding editor of the Hong Kong University Press book series, Asian Englishes Today, co-editor of the Wiley-Blackwell journal World Englishes, and an editorial board member of the journals Educational Studies, English Today, English World-Wide. From 2003 to 2004, he served as elected President of the International Association for World Englishes (IAWE).