This book explores the nature of finiteness, clarifying what it is and establishing its usefulness and limitations. Leading scholars look from a range of perspectives at how finiteness is conceived in formal and functional theories of grammar; at its cross-linguistic manifestations; at the finite/nonfinite opposition in individual languages; and at the role of finiteness in linguistic change and linguistic development. The book is written and structured to appeal to scholars and students of syntax and general linguistics at graduate level and above.