This groundbreaking book offers a new and compelling perspective on the structure of human language. The fundamental issue it addresses is the proper balance between syntax and semantics, between structure and derivation, and between rule systems and lexicon. It argues that the balance struck by mainstream generative grammar is wrong. It puts forward a new basis for syntactic theory, drawing on a wide range of frameworks, and charts new directions for research. In the past four decades, theories of syntactic structure have become more abstract, and syntactic derivations have become ever more complex. Peter Culicover and Ray Jackendoff trace this development through the history of contemporary syntactic theory, showing how much it has been driven by theory-internal rather than empirical considerations. They develop an alternative that is responsive to linguistic, cognitive, computational, and biological concerns. Simpler Syntax is addressed to linguists of all persuasions. It will also be of central interest to those concerned with language in psychology, human biology, evolution, computational science, and artificial intelligence.