Research on language development has often been focused on child language learning, and is usually restricted to monolingual learners. Relatively little attention has been given to language development beyond early childhood. However, changing lifestyle patterns and life events increasingly suggest that developing a linguistic repertoire remains important throughout the years of middle childhood, adolescence and adulthood. Emphasis on multi-literacies and Internet communication has reinforced the need for people not only to develop the languages they already know, but to learn new languages in order to maintain and develop ever broadening relationships. This title provides an introduction to language development that differs from existing books in that it traces language development and cognitive development (together with the associated debates) from babyhood, through the school years of middle childhood and adolescence, into adulthood and the world of work. As the world trend is towards learning to speak, read and write more than one language, this comprehensive text includes descriptions and discusssions of learning more than one language sequentially and simultaneously. The authors of this text draw on the multicultural and multilingual contexts where they have lived, worked and researched to provide an introductory text for students of language and lingusitics. Each chapter includes ideas and suggestions for students to follow-up and begin their own small-scale investigations into language development.