This article takes stock of the basic notions of Information Structure (IS). It first provides a general characterization of IS following Chafe (1976) within a communicative model of Common Ground (CG), which distinguishes between CG content and CG management. IS is concerned with those features of language that concern the local CG. It then defines and discusses the notions of Focus (as indicating alternatives) and its various uses, Givenness (as indicating that a denotation is already present in the CG), and (...) Topic (as specifying what an statement is about). It also proposes a new notion, Delimitation, which comprises contrastive topics and frame setters, and indicates that the current conversational move does not satisfy the local communicative needs totally. It also points out that the rhetorical structuring partly belongs to IS. (shrink)