Abstract
This article investigates the proactive behavior of the firms in a dominant position within the new approaches of competitive behavior. The case of the French exploitation of cinematography makes clear the way in which the leaders combine collective actions effectively in the redefinition of the rules with individual initiatives of disturbance. It is not effective to play the same play better. Instead, one needs to play fundamentally differently in order to disadvantage the competitors., Cet article s'interroge sur le comportement proactif des firmes en position dominante à partir des nouvelles approches de la concurrence. Le cas français de l'exploitation cinématographique éclaire la façon dont les leaders combinent efficacement actions collectives de redéfinition de règles avec initiatives individuelles de pertubation.