Book excerpt: This collection brings together leading names in the field of bilingualism research to celebrate the 25th anniversary of the Studies in Bilingualism series. Over the last 25 years the study of bilingualism has received a tremendous amount of attention from linguists, psychologists, cognitive scientists, and neuroscientists. The breadth of coverage in this volume is a testament to the many different aspects of bilingualism that continue to generate phenomenal interest in the scholarly community. The bilingual experience is captured through a multifaceted prism that includes aspects of language and literacy development in child bilinguals with and without developmental language disorders, language processing and mental representations in adult bilinguals across the lifespan, and the cognitive and neurological basis of bilingualism. Different theoretical approaches – from generative UG-based models to constructivist usage-based models – are brought to bear on the nature of bilingual linguistic knowledge. The end result is a compendium of the state-of-the-art of a field that is in constant evolution and that is on an upward trajectory of discovery.