Résumé
A role-playing game (RPG), KatAware, was developed in the Kat River catchment of South Africa to support the negotiation process among water users on the allocation rules of the resource. Playing the RPG with local stakeholders exhibited some regularity in the behaviour of players, particularly on their attitude of defining binding agreements. These regularities were first formalized through a model of cooperative game theory (CGT), and then, to confirm the results of the model, tested by an experimental protocol. Both the model and the protocol were based and calibrated on the results of the RPG. The progressive simplification (decontextualization) required to bring the RPG into the laboratory suggested to explore the role of context (in our case water related issues) on players' behaviour. The objective of this paper is to illustrate the process that conducted the research team from the experience in the Kat River to the first experiments to test the hypotheses exhibited in the experience and then to analyze the influence of context on players' behaviour. Terms and concepts are clarified in order to provide a clear research framework in this new field at the border between experiences and experiments in social sciences for commons management. (Résumé d'auteur)