It is a commonplace to say that the meaning of text is more than the conjunction of the meaning of its constituents. But what are the rules governing its interpretation, and what are the constraints that define well-formed discourse? Answers to these questions can be given from various perspectives. In this edited volume, leading scientists in the field investigate these questions from structural, cognitive, and computational perspectives. The last decades have seen the development of numerous formal frameworks in which the structure of discourse can be analysed, the most important of them being the Linguistic Discourse Model, Rhetorical Structure Theory and Segmented Discourse Representation Theory. This volume contains an introduction to these frameworks and the fundamental topics in research about discourse constraints.