This volume, in its 25 definitive chapters on normal and nonnormal language development, represents the authoritative and up--to--date complete sourcebook on child language development. All aspects of child language development are addressed, including phonetics, phonology, grammar, and lexical development. Connectionism and government--binding theory, as applied to language development, are fully represented. The relevance of input, cognition, and social factors to language development is explored. Chapters on methodology, particularly using computer databases, are provided for both normal and nonnormal acquisition.