The thiotungstate [Et4N](2)[OW(WS4)(2)], [Et4N](2).1, containing the linear [{S2WVI(mu-S)(2)}(2)W-IV=O] core, was prepared from [Et4N](2)[WS4] in the presence of the sulfide scavenger Cd2+. Addition of 1,2-bis(o-diphenylphosphinophenyl)-ethane (diphosphine) and Cu+ or Ag+ to solutions of 1 in MeCN/DMF led to coordination of the (diphosphine)Cu/Ag fragments to the terminal sulfido ligands of 1, yielding novel linear pentanuclear, heterometallic clusters [mu-{OWIV(DMF)((WS4)-S-VI)(2)}{M(diphosphine)}(2)], 2 (M = Cu) and 3 (M = Ag). Along with 2, the trinuclear cluster [{mu-((WS4)-S-VI){Cu(diphosphine)(2)}], 4, was also obtained. The molecular and crystal structures of [Et4N](2).1, 2-MeCN, 3-MeCN, and 4.2MeCN.CH2Cl2 have been determined.