Description: Surprise and Concerted Action: An inquiry into changing patterns of interaction in communicative situations where lived experience breaks the monopoly of authoritative knowledge.This paper discusses some surprising turns in a communicative situation with the help of such conceptions as "acting in concert", "authoritative knowledge", "new meaning" and "surprise". It reflects upon the experiences from a study of the communication in medical group consultations aiming at a better tapering, where those taking part all the more brought lived experiences into the situation, thus acting "in concert" and setting authoritative knowledge aside, taking themselves and each other by surprise, and constructing new meaning. The discussion is based upon ideas about communication and meaning (G H Mead 1967); human action as public appearance (H Arendt 1998); and intersubjectivity in learning and authority in knowledge (M von Wright 2000, 2004). Methodology: The paper is an educational philosophical inquiry into the domains of participation, learning and meaning brought forward by the results from the following empirical research: The group consultation was studied through participatory observation and interviews from the viewpoint of participation, meaning making and learning in communicative situations, and the setting itself is understood as a figuration (von Wright 2000, N Elias 1991). (Also (2) the patients' clinical data, intake of medicine, and laboratory results were gathered and analyzed, and compared with a control group, E van Mansvelt) Conclusions: The present analysis of the communicative situation is not trying to explain the statistically significant medical results. Instead it tries to generate a theoretical framework for discussing and analyzing the inter-action in communicative situations of learning outside traditional educational settings, and for conceptualizing the complex phenomena, which is usually called "shared decision making" between patients and doctors.