Biliteracy - the use of two or more languages in and around writing- is an inescapable feature of lives and schools worldwide, yet one which most educational policy and practice continue blithely to ignore. The continua of biliteracy featured in the present volume offers a comprehensive yet flexible model to guide educators, researchers, and policy-makers in designing, carrying out, and evaluating educational programs for the development of bilingual and multilingual learners, each program adapted to its own specific context, media, and contents.