This paper analysis the juridic system of the Brazilian co-operative societies and the French agricultural co-operative societies, from their most remarkable principle: the twofold quality of both owner and user of the members of these societies. It was verified how the society's engagement and the cooperation engagement is done in both countries, presenting the contrasts and the convergences between the two juridic systems, with the finality to contribute to the modernization of the Brazilian co-operative law system, as well as the French. There were highlighted the new ways of capital reinforcement as the practiced in France and the notion of the Brazilian co-operative act, unknown to France. The adoption of the French model of co-operative contract was suggested as an alternative to the Brazilian system, in a sense of guaranteeing the stability of the operational engagements done to both the co-operative society and the co-operators. As to the acceptance of the elements of the co-operative act, such as the practiced in Brazil, will also be able to be revealed as an important mechanism in France, related to the qualifying process of the co-operational contract.
