The contributions to this volume address the model of diachronic language comparison that has emerged from the field of contrastive linguistics. The volume's aim is to use language comparison to derive principles of language change that allow for generalizations that go beyond single languages. Indeed, the phenomenon of change observed in a particular language is thrown into sharper relief when compared to comparable developments in other languages. Such a comparison also facilitates the identification of change that is highly specific to a single language. The articles in the volume illustrate the relevance of these concepts for phonological, morphological, and syntactic changes.