Noam Chomsky is not only one of the most influential, but also one of the most controversial figures in Twentieth century linguistics. In view of the polarization of opinions on Chomsky, giving a balanced account of Chomskyan linguistics is an ambitious venture. This book describes both Chomskyan linguistics and the positions defended by its opponents in terms of research programs. A research program consists of a number of assumptions on what language is and how it should be studied. Only by assuming that research programs adopted by a large number of scholars for a prolonged period have to be rational, coherent systems can we hope to fully understand the nature of the conflicts between them. After a general discussion of the notion of a research program, this volume demonstrates how the various stages of Chomskyan theory can be analyzed as belonging to a single, coherent research program. This research program is then compared to those for Post-Bloomfieldian linguistics, Lexical-Functional Grammar, Generalized Phrase Structure Grammar and Montague Grammar, and Head-Driven Phrase Structure Grammar. Finally, this book addresses the relevance of the research program of Chomskyan linguistics for the practical study of the acquisition, change and use of language.