In this textbook Shelia Kennison provides a comprehensive introduction to the field of language development. Taking a broad perspective that covers the period before birth through old age, Kennison covers all of the many facets of this exciting field. Throughout the text there is a strong integration of world languages and bilingualism; the biological basis of language (including cognitive neuroscience and the socio-cultural influences on language); language development across cultures; grammatical development; and language-related delays and disorders.