Court hearings, of which this article presents an analysis, are situations characterized by controversy and by accusation and defence. Yet can we affirm that all trust has left this type of situation? A praxeological approach to action - which questions the key role of deliberation, decision-making, intention, interpretation and normative frames in its analysis - enables us to see how trust is intrinsic to all interaction. The coordination of interaction, accomplished on the combined basis of routine actions and production of visibility, gives actors the bases for the contact. After describing the interactional mode of a court hearing, the author makes a detailed analysis of a related device: "ajours" or openings in the prosecutor's speech, in which the defendant talks briefly. These enable the actors to know and to make known the people and things with whom and with which they are dealing, and to devise a common mode of interaction. These observations lead to the definition of practical trust - produced sequentially in a concerted and observable way - indissociably linked to the coordination of action.