This article presents a case study of a Norwegian hospital, analysing how health professionals manage conflicts related to work co-operation. Altogether, 29 health professionals working in the hospital were interviewed, and data was analysed according to a grounded theory approach. When in conflict, health professionals seem to use three major approaches to handling the situation: avoidance, forcing and negotiation, and usually in that order. Avoidance behaviour or suppression is the most common reaction to an emerging conflict. If the use of power does not re-establish a balance between the participants, one negotiates. These conflict styles seem to be determined by two major factors: the perceived interdependence between parties and the perceived urgency of doing something about the situation. Nurses and physicians in particular seem to differ considerably in their perception of what is a conflict and when to do something about it. Such differences in perceptions and the extensive use of avoidance represent important challenges to managers and clinical leaders when it comes to advancing interprofessional co-operation.