ABSTRACT
In this third decade of the 21st century, it is clear that the world’s citizens increasingly function in more than one language – and more and more individuals acquire more than one language from birth or in early childhood. What is more, language skills are essential to a child’s ability to communicate and develop. This chapter’s primary goal is to underscore the variability of the bilingual experience in infants and young children, in terms of both language experiences and language outcomes. The available interdisciplinary evidence on infant and childhood bilingualism is critically discussed to provide an up-to-date picture of which factors promote the acquisition of two or more languages in infancy and childhood. A particular emphasis is placed on the powerful changes of early exposure to two languages on the development, structure, and functioning of a newborn’s/infant’s brain.
