This is a wide-ranging and multi-disciplinary discussion of the connections between language, borders and identities. Looking at a broad, geographically diverse spectrum of border contexts, this volume illustrates a range of methodological approaches. It examines political borders that divide monoglossic and heteroglossic territories, as well as regional and local and symbolic borders. The authors assess the linguistic implications of these borders contexts such as language planning and policy (e.g. for multilingual education and protection of minority languages) and border control (via the chapter on language analysis for the determination of origin, 'LADO'). Each border is unique, making generalisations about how language functions in 'borderlands' difficult to formulate but casting the net as wide as we intend will, however, equip us to develop and refine models of how language is used to construct borders, and to indicate on which side of a border speakers situate themselves. It covers political, socio-psychological and symbolic borders. It takes a multi-disciplinary approach by combining sociolinguistic research with human geography, anthropology and social psychology. It uses international case studies and examples throughout.