Norbert Elias’ theory of the civilizing process proves to be a precious contribution to explaining, in the period between the wars, the relaxation of body behavior as best seen in beach behavior. In spite of its limits, it sets the historian on the path of the relations established between summer practices of nudity and relaxation, the exaggerated control of emotions and the transformation of the social relations the theory serves. The ease of showing oneself, of making light of modesty is part of the historical promotion of ways of behavior (in particular of behaving naturally and spontaneously) in the organization and reorganization of social classifications and exchanges. The resistance to this reclassification that culminates in the wake of February 1934 can explain the different ways a sense of this relaxation can be understood. This article thus combines historical elucidation and methodological reflection.