She has lectured widely in Europe, North America, and Japan, and published numerous scientific articles and book chapters on sociolinguistics and psycholinguistics of bilingualism and second language acquisition. She is an author of Emotions and Multilingualism (Cambridge University Press, 2005), co-author of Crosslinguistic Influence in Language and Cognition (with Scott Jarvis; Routledge, 2008), editor of Bilingual Minds (Multilingual Matters, 2006) and co-editor of Negotiation of Identities in Multilingual Contexts (Multilingual Matters, 2004).