International audienceRelationships between decision process and action in real world conditions emerge as a key issue in elite sport as well as in organization studies. When pressure is high and environment is evolving rapidly, acting despite a limited situation awareness is common. In such stressed situations, the observation of phenomenon raises methodological difficulties such as the access to information and its validation with regard both to the decision-making process of the decision-maker and concurrently to the course of action. Studying in real time decision processes of a professional skipper at work during an ocean yacht race from the viewpoint of the router embedded in the skipper's team provides an opportunity to go forward in understanding relationships between decision processes and action in real world when phase shifts occur. The methodological choices are discussed and research directions for further real world researches are proposed