is Chair of Applied Linguistics and Director of the UCL Centre for Applied Linguistics at the UCL Institute of Education, University College London, UK, and a Fellow of the Academy of Social Sciences, UK. His research interests are in the broad areas of bilingualism and multilingualism. He has published extensively in journals ranging from Applied Linguistics, Modern Language Journal, Journal of Pragmatics, Language in Society to Language, Cognition and Neuroscience, and Clinical Linguistics and Phonetics. He is Principal Editor of the International Journal of Bilingualism (Sage, SSCI, AHCI) and Applied Linguistics Review (De Gruyter, SSCI, AHCI) and series editor for ‘Research Methods in Language and Linguistics’ (Wiley-Blackwell). His recent publications include The Cambridge Handbook of Linguistic Multi-Competence (with Vivian Cook, 2016) and Translanguaging: Language, Bilingualism and Education (with Ofelia Garcia, 2014) which won the 2015 British Association of Applied Linguistics (BAAL) Book Prize.