Numerous works in industrial organization and ecology of organizations have raised recently the question of the link between age and mortality of an organization. The paper tests four theoretical propositions about this link. We compare the survival of the French agricultural cooperatives with their competitors. We apply a semiparametric duration model for discrete time (cloglog) taking into account unobserved heterogeneity and isolating the age and the period effects. The study shows the specific temporal dynamics of cooperatives. Some explanations of this result are derived from insights on the competition between organizations.