Presupposing the Logical Description Grammar of van Leusen & Muskens (2003, Meaning, the Dynamic Turn), we present an analysis of corrections in discourse. In line with Asher (1995, Proceedings of the Conference on Semantics in Context) it is argued that the defining characteristic of corrections is incompatibility: corrections require the presence of a contextually supported alternative to the corrective claim such that the two are inconsistent in the context of interpretation. A large range of accommodation and pragmatic strengthening effects is accounted for in terms of this requirement.