Reaction of potassium N-R-Sulfonyldithiocarbimates, K2(RSO2N = CS2) (R = Me, Ph, 4-MeC6H4, 2-MeC6H4, 4-ClC6H4, 4-BrC6H4), with CoCl2·6H2O, yielded the complex CoIII anions [Co(RSO2N = CS2)3]3−, which were isolated as their Bu4N+ salts. Elemental analyses, i.r. spectra and u.v.-vis. data were consistent with the formation of cobalt-sulfur diamagnetic octahedral (D3) complexes. The 1H and 13C n.m.r. spectra showed the expected signals for the Bu4N+ cation and the dithiocarbimate moieties. The 1H n.m.r. integrations were consistent with a 3:1 cation:anion ratio.