This volume of the Encyclopedic Handbook presents, for the first time in the German-speaking world, a comprehensive overview of central theories, conceptual approaches, and content in the fields of language and communication, alongside their application-oriented questions, beyond the classical special education disciplines. National and international experts in semiotics, linguistics, neuroscience, developmental psychology, phoniatrics, and paediatric audiology, as well as language didactics and speech therapy, discuss the current state of knowledge and research for teaching, therapy, and support. The thematic spectrum covers sound and written language acquisition, sign language, and supported communication, as well as multilingualism and German as a second language. Additionally, the transitions between areas of support, such as hearing and learning, are addressed.