Focuses for the first time on materials development and applications of current research and theory for the main areas of applied linguistics (e.g. second language acquisition, pragmatics, vocabulary studies). There are many books on applied linguistic theory and research and there are now a number of books on the principled development of materials for language learning, but this book takes a new approach by connecting the two concerns. Each of its chapters first of all presents relevant theories and research conclusions for its area and then considers practical applications for materials development. The chapters achieve these applications by reporting and commenting on current theory and research, by analysing the match between current published materials and current theory and by suggesting and exemplifying applications of current theory to materials development. This will be an essential resource both for those studying or teaching materials development and for those studying or teaching applied linguistics.