The critical approach of peace and conflict theory (Kritische Friedens-und Konfliktforschung) purports to criticize the society as a whole by analyzing its structure. In contrast, the behavioral approach endeavors to discover the empirical regularities. These two approaches are being integrated into the so-called 'constructive' approach, which will be the main trend in the field. Endorsing the constructive approach this paper examines both the critical and behavioral approaches in a comparative perspective in order to locate the central theme in the peace and conflict researches. Peace and conflict theory has summed up the various methods of the behavioral science, and it has formulated a criticism to the effect that they might be easily expanded and applied from one level to the other. Peace and conflict researchers have pointed out the 'gaps of theory' in the behavioral study of conflicts and the disregard of symmetry/asymmetry problems. Thus. Prof. D.Senghaas of West Germany has contrived a typology of conflict formations in the contemporary world, which should shed some light upon the conflict-ridden structure. This leads us t o a structural reformation of the contemporary international system, and the urgent necessity for the peace and conflict theory shall be an identification of how to deal with the problem of war, the keenest manifestation of conflicts. Therefore, peace researches henceforth are bound to criticize the advanced countries more radically and to focus more attention on the Third World, along with a more explicit developoment of the conflict formation theory and the conflict resolution methods. The d6construction approach in conflict theory ought to maintain firmly the following standpoints in its contribution to the peace research: that War is an organized crime, and that the Third World has bee the object of oppression.