After introducing the phenomenon of presupposition, the paper presents the influential Stalnakerian account, and makes some criticisms, pointing out that the well-known practice of informative presupposition puts heavy strain on Stalnaker's pragmatic characterization of the phenomenon, in particular of the triggering of presuppositions. Stalnaker has replied to previous criticisms by relying on the well-taken point that we should take into account the time at which presupposition-requirements are to be computed. In defense of a different, ‘semantic’ (in a sense) and normative account of the phenomenon of presupposition, the paper argues that that point does not suffice to rescue the Stalnakerian proposal, and portrays Lewisian ‘accommodation’ as one way in which speakers adjust themselves to one another in the course of conversation.

Keywords: presupposition, accommodation, Stalnaker’s account of presupposition, presupposition triggers, normative speech acts