This book investigates the nature and consequences of universal principles in four major grammar components, i.e. syntax, phonology, morphology and semantics. Language specific parameters are held responsible for the attested variation. The papers collected in this book analyse selected phenomena from English, Hungarian, Irish, Italian, Japanese, and Polish, and shed new light on the interaction of universals and parameters in the structure of individual language systems. The generative framework is adopted as the theoretical model in the majority of contributions.