This collection brings together theory and ethnographic research from a range of national contexts to offer unique insights into the nature of agency in language policy and planning. Situated within a broader sociological framework, the book explores agentive processes at work in case studies from around the world, engaging in discussions of such key themes as language and identity, language ideologies, linguistic diversity in education, and language revitalization. Each chapter examines the ways in which decisions made at both the local and national level impact language use and in turn, the dynamic relationship between language use, policy, and practice in these contexts. Taken together, this volume advances our understanding of agency in language policy and planning and directions for future research, making this key reading for students and scholars in language and education, critical sociolinguistics, and applied linguistics.