This book focuses on bilingualism in the context of migration and minorization processes. Its aim is to integrate recent research in this fast growing field of scientific and social interest into a single and coherent academic reference. The book has four parts. Part One goes into processes of early bilingual development. Part Two focuses on bilingual development of children at school age. In Part Three the constraints in processes of code-switching and borrowing are dealt with. Part Four discusses the issues related to processes of language maintenance and language loss. Taken from these four perspectives, the volume offers a comprehensive state of the art, with contributions from different combinations of language parts.