This volume reconsiders the problem of context in language testing and other modes of assessment from the perspective of transdisciplinarity. Transdisciplinary assessment research brings together collaborators who draw on the strengths of their differing backgrounds and expertise in order to address high-stakes complex socially-relevant problems. Traditional treatments of context in language assessment research have generally been informed by individualist cognitive theories within measurement and psychometrics. The additive potential of alternative social theories, including theories of genre, situated learning, distributed cognition, and intercultural communication, has largely been overlooked. In this book, the benefits of socio-theoretical reconsiderations of context are discussed and further exemplified in transdisciplinary research studies that investigate the use of assessment in classroom and workplace settings. The book offers a renewed view of context in arguments for the validity of assessment practices, and will be of interest to assessment researchers, practitioners, and students in applied linguistics, education, educational psychology, language testing, and other related disciplines and fields.