It is shown that the notions of aggressive behavior as 'intentional emission of noxiow stimulation' (Buss, 1961(Buss, , 1963(Buss, , 1966(Buss, , 1971 and that of 'injuriating goal response ' (Dolknd, Doob, Miller, Mower and Sears, 1939) are identical. The usefulness of these theories to predict S's reaction to the reception of a given noxious stimulation is questioned. I t is suggested that S's reactions to noxious stimulation may or may not be aggressive, depending on whether the noxious stimulation S receives is interpreted as being a behavior justified by the n o m in the situation, or as reflecting an aggressive intent of 0. I t is hypothesized that the norms established in the situation depend on (i) victim's perception of the noxious stimulation received as being instrumental for 0 s goal attainment, (ii) victim's perception of the value of 0 s goal, and (iii) the value of victim's own goal. The establishment of norms regulating the exchange of noxious stimulation between Ss is operationalized in two experiments. Aggression, defined as an infringement of these norms, is measured. In Experiment I, participate 56 female students, and in Experiment 2, 80 male students. Subject is alternately victim (he performs a sensori-motor task and receives an electric shock) and aggressor (he shocks the other S ) . In Experiment I it is found that Ss counteraggress faster and more frequently if they interpret the shock received from the partner as an infringement of the norm. In Experiment 2, Ss do not counteraggress more * In preparing this paper we were greatly assistance in execution of the experiments, helped by the fruitful discussions with we are indebted to Miss FranfoisaMarie members of the staff from the Labratoire F&al and Miss May Veldhuis.de Psychologie Sociale in Paris, especially +* Experiment 2 was designed and con-Robert Pages, and members of the Depart-ducted while the author was a student in ment of Social Psychology in Nijmegen,