Book excerpt: This book represents a major statement of the current research being conducted on the learning of second languages from a sociocultural perspective. The book is divided into a theoretical and an empirical part. Specific topics covered include: learning and teaching languages in the zone of proximal development; L1 mediation in the acquisition of L2 grammar; sociocultural theory as a theory of second language learning; gestural mediation in a second language; and constructing a self through a second language.