This reader presents key contributions from the past three decades of bilingualism research, demonstrating the trajectory of key themes and areas of study. Celebrating 30 years of Multilingual Matters' Bilingual Education and Bilingualism book series, the chapters offer an overview of key developments in the field to date. The book focuses on four strands which have emerged over the course of the series: bilingual children and family language policy, multilingualism in the classroom, bilingual immersion education and language policy and advocacy. This reader offers students and researchers a deeper understanding of how the field has evolved, current issues in bilingual education, and the implications for both practice and future research.