I. Introduction -- I.1 The Study of Language -- I.2 The Competence-Performance Distinction -- I.3 The Universal Parser -- I.4 A Programme of Research -- I.5 Organisation of Chapters -- II. Perspectives on Sentence Processing -- II.1 Modularity in Language Processing -- II.2 The Nature of the Empirical Evidence -- II.3 Extant Theories of Linguistic Performance -- II.4 Conclusions -- III. Principles, Parameters and Representations -- III.1 Explanation in Universal Grammar -- III.2 The Transformational Model -- III.3 Representations: Types vs. Levels -- III.4 Summary and Discussion -- IV. A Principle-Based Theory of Performance -- IV.1 The Foundations of the Processing Model -- IV.2 The Nature of Processing Complexity -- IV.3 Modularity in the Syntactic Processor -- IV.4 The Phrase Structure Module -- IV.5 The Thematic Module -- IV.6 The Chain Module: Recovering Antecedent-Trace Relations -- IV.7 Summary -- V. A Logical Model of Computation -- V.1 Principle-Based Parsing -- V.2 A Logical Model of Performance -- V.3 Control in the Syntactic Processor -- V.4 Summary and Discussion -- VI. The Specification of Modules -- VI.1 The Phrase Structure Module -- VI.2 The Chain Module -- VI.3 The Thematic Module -- VI.4 Summary -- VII. Summary and Discussion -- VII.1 A Summary of the Theory -- VII.2 Computational Properties of the Model -- VII.3 The Innate Sentence Processor -- VIII.Conclusions -- Index of Authors -- Index of Subjects.