This is the long-awaited third edition of Chomsky's outstanding collection of essays on language and mind. The first six chapters, originally published in the 1960s, made a groundbreaking contribution to linguistic theory. This new edition complements them with an additional chapter and a new preface, bringing Chomsky's influential approach into the twenty-first century. The final chapter revisits the key issues, reviewing the 'biolinguistic' approach that has guided Chomsky's work from its origins to the present day, and raising some novel and exciting challenges for the study of language and mind.