The difference in magnetic susceptibility of graphite and diamond prompted Raman to postulate the flow of currents around the ring system of graphite in response to an applied magnetic field. The discovery of new carbon allotropes, the fullerenes, has furthered our understanding of this phenomenon and its relationship to aromatic character. C-60 and the other fullerenes exhibit both diamagnetic and paramagnetic ring currents, which exert subtle effects on the magnetic properties of these molecules and provide evidence for the existence of pi-electrons mobile in three dimensions.