In order to enrich dynamic semantic theories with a `pragmatic' capacity, we combine dynamic and nonmonotonic (preferential) logics in a modal logic setting. We extend a fragment of Van Benthem and De Rijke's dynamic modal logic with additional preferential operators in the underlying static logic, which enables us to define defeasible (pragmatic) entailments over a given piece of discourse. We will show how this setting can be used for a dynamic logical analysis of preferential resolutions of ambiguous pronouns in discourse.