Requests, greetings, complaints, offers and invitations are some of the many action types routinely invoked in the description and assay of interaction. But what is their ontological status ? It is suggested that action is conduct under a description. Thus, for the bigger part, interaction is organized independently of any action description or categorization of conduct into discrete action types. Instead, interactional participants use the details of the situation in which they find themselves in to generate conduct that others will identify and to which they are able to reply in fitted ways. ‘Action’ still plays a crucial role in interactional organization, however, as accountability attaches not to raw conduct but only to conduct under some specific, action-formulating description.