The study of the relationships between identity and multilingualism is more timely than ever in view of the fact that most of the world’s population is multilingual and that globalization of economies and intensification of migration have facilitated a mixture of languages, cultures and identities to an unprecedented degree. This paper shows how at both the macro- and micro- sociolinguistic level language has probably always played and will continue to play a critical role not simply in articulating identities, but also in actively constructing them as speakers make choices in their social interactions in favor of some varieties over others (and likewise, within those varieties, of some variant forms over others). Macro-level processes such as language maintenance and shift are the long-term, collective consequences of consistent patterns of language choices (both conscious and unconscious) made by speakers at the micro-level. Thus, the everyday forces that shape people’s linguistic repertoires are the same ones that drive language change and the evolution of language more generally. The paper concludes with some reflections on why identities matter and identifies some of the challenges ahead.
 We live in a world where identity matters. It matters both as a concept, theoretically, and as a contested fact of contemporary political life. The word itself has acquired a huge contemporary resonance, inside and outside the academic world (Gilroy 1997: 301).