This book offers a new and in-depth analysis of English conditional sentences. In a wide-ranging discussion, Dancygier classifies conditional constructions according to time-reference and modality. She shows how the basic meaning parameters of conditionality correlate to formal parameters of the linguistic constructions which are used to express them. Dancygier suggests that the function of prediction is central to the definition of conditionality, and that conditional sentences display certain formal features which correlate to aspects of interpretation. Although the analysis is based primarily on English, it provides a theoretical framework that can be extended cross-linguistically to a broad range of grammatical phenomena.