The papers in this volume reflect the renewed interest in the semantics of grammatical categories and the issues of invariance and variation in grammar. In particular, this collection presents the current understanding of invariance of grammar with respect to the synchronic and diachronic analyses of specific languages, and as realized in work on typology and universals.The book is divided into five sections: The Question of Invariance; Invariance and Grammatical Categories; Grammar and Discourse; Grammar and Pragmatics; Typology and Universals.