The paper sketches the place of dynamic semantics within a broader picture of developments in philosophical and linguistic theories of meaning. Some basic concepts of dynamic semantics are illustrated by means of a detailed analysis of anaphoric definite and indefinite descriptions, which are treated as contextually dependent quantificational expressions. It is shown how a dynamic view sheds new light on the contextual nature of interpretation, on the difference between monologue and dialogue, and on the interplay between direct and indirect information.