This volume provides the reader with an up-to-date overview of the emerging debates over the role of language rights and linguistic diversity within political theory. It brings together many of the leading political theorists who work in the field, together with some of the most important social scientists, with the aim of exploring how political theorists can conceptualize issues of language rights and contribute to public debates on language policy. The thirteen essays in this volume highlight both the empirical constraints and normative complexities of language policy, and identify the important challenges and opportunities that linguistic diversity raises for contemporary political theory.