Bernard PULLMAN During a long period organic chemistry was one of the pre ferred field of exploration for many quantum chemists. It still remains of major interest for a number of them, but altogether it seems as if the center of gravity of the quantum molecular theories became displaced towards different horizons. The dis placement seems in fact to occur in two directions. On the one hand, we see a prominent development of very refined computations for relatively small and frequently inorganic molecular systems with the view of a better and better reproduction of their obser vable properties...