This book defines the notion of applied sign linguistics by drawing on data from projects that have explored sign language in action in various domains. The data sources have been drawn from various studies on sign language research, teaching, assessment and interpreting that have been conducted by the two co-authors. As well as defining key concepts and giving an overview of existing research, the book provides clear guidance on conducting applied sign linguistics research, with suggestions for new research topics. The book is targeted at sign language and sign language interpreting students, sign language teachers, researchers, interpreter practitioners and educators, Deaf Studies teachers and students, educators working with deaf children, and policy makers. It will also be of interest to other people working with minority language communities and to scholars and practitioners in applied linguistics research more generally.