According to the interactional form of the professional dominance (PD) thesis professional service encounters, especially of the medical sort, are arenas of negotiation, conflict or struggle in which professional service providers attempt to dominate lay service seekers through various verbal strategies for controlling the definition of the situation, the interactional agenda and the time and resources expended in the encounter. Prominent among these purported linguistic strategies are the use of interruptions, questions (and particular types of questions) and silences. Service seekers are correspondingly said to resist such attempts at control. In this paper we criticize the PD thesis as it applies to interruptions and questions through a brief re-examination of some of the analyses by C. West and by Scheff of medical and psychiatric encounters, and through a longer scrutiny of a corpus of calls to the police. Not finding any evidence of these verbal control strategies we propose an alternative ethnomethodological (conversation-analytic) account of the occurrence of overlaps (in West’s data) and of the so-called ‘abruptness’, ‘constraining influence’ and ‘asymmetry’ of questions in calls to the police. We locate these apparent features in a general account of the interactional shape of the calls, an account which sees that shape as a concerted accomplishment of the parties to them. That accomplishment, we claim, derives from the parties’ mutual orientation to (a) the occasion of the call as one directed to the performance of a set of tasks, which establish (b) the relevance of co-identification in terms of a particular set of identities and (c) a characteristic distribution of speakers’ rights to turns at talk. While not disputing (here) the structural version of the PD thesis we wish to replace the interactional version of it by an approach which begins to address how the institutional interaction reproducing that structure is produced as such in the first place.