The use of simulation as an educational tool is becoming more widespread in healthcare. Such training gathers doctors and nurses together, which is a rare opportunity in such a sector. The present research focuses on the contribution of inter-professional training for the development of collaborative skills when managing an emergency situation in the context of anesthesia or intensive care. From direct observations of post-simulation debriefing sessions and interviews held with learners in postgraduate or in-service training, either in single or multi-professional groups, this study shows that these sessions, based on experiential learning and reflective practice, help to build a shared vision of the problem and of common operative patterns, supporting better communication and the “ability to work in a team.”