The differriosulphane {CpFe(CO) 2} 2(μ-S)_) 1) can easily be prepared by the reaction of CpFe(CO) 2Cl with S(SiMe 3) 2. The nucleophilicity of the bridging sulphur atom in 1 is established by the addition of the electrophilic complex cation [CpFe(CO) 2] +, giving the trinuclear complex [{CpFe(CO) 2} 3S]Cl ( 2), which can also be prepared by the reaction of S(SiMe 3) 2 with an excess of CpFe(CO) 2Cl. Oxidation of 1 yields the SO 2 complex 4, which easily eliminates one CO group by photolysis to form the CO-bridged complex 5. The triferriosulphonium salt 2 decarbonylates, too, and gives 6 containing one FeFe bond and one CO bridge. The reaction of {CpFe(CO) 2} 2 with the sulphur chlorides SCl 2 or SOCl 2 leads to the formation of ionic S-functionalized species. The sulphur-containing fragments SCl or SOCl insert into the FeFe bond to give the chloro-substituted differiosulphonium or differriosulphonium salts [{CpFe(CO) 2} 2 SCL]Cl ( 7) or [{CpFe(CO) 2} 2S(O)Cl]Cl ( 8). The mass, IR and NMR spectra of 1–5) are reported and discussed.