Barbara's research interests have centred on empirical and quantitative studies of English speech communities, particularly those that include ethnic varieties of English resulting from in-migration or which were originally bilingual speech communities. Before joining the University of Sydney Linguistics Department in the mid-70s, she studied Mexican children in Los Angeles and African-American, Anglo and Mexican children in Lansing, Michigan. The Sydney speech community provided the opportunity to study the impact of recent widespread migration (Italians and Greeks) on Australian English, building on the work of A. G. Mitchell, Arthur Delbridge and John Bernard. After retiring from Sydney University, she collaborated with Sylvie Dubois from Louisiana State University for ten years on the study of Cajun English. Most recently, with Ronald Horvath, she analysed a language change in progress in nine cities - five in Australia, three in New Zealand, and one in England (London) with the aim of integrating sociolinguistics and dialect geography. Barbara received an MA from Michigan State University and a PhD from Georgetown University.