In this handbook, renowned scholars from a range of backgrounds provide a state of the art review of key developmental findings in language acquisition. The book places language acquisition phenomena in a richly linguistic and comparative context, highlighting the link between linguistic theory, language development, and theories of learning. The book is divided into six parts. Parts I and II examine the acquisition of phonology and morphology respectively, with chapters covering topics such as phonotactics and syllable structure, prosodic phenomena, compound word formation, and processing continuous speech. Part III moves on to the acquisition of syntax, including argument structure, questions, mood alternations, and possessives. In Part IV, chapters consider semantic aspects of language acquisition, including the expression of genericity, quantification, and scalar implicature. Finally, Parts V and VI look at theories of learning and aspects of atypical language development respectively.