The reactivity of the phosphinito bridged Pt(I) complex [(PHCy(2))Pt(1)(μ-PCy(2)){κ(2)P,O-μ-P(O)Cy(2)}Pt(2)(PHCy(2))](Pt-Pt) (1) towards Au(I) and Ag(I) electrophiles was explored. Treatment of 1 with AuCl yielded the dichloro Pt(II) complex [(Cl)(PHCy(2))Pt(μ-PCy(2)){κ(2)P,O-μ-P(O)Cy(2)}Pt(Cl)(PHCy(2))] (4), while [Au(PPh(3))Cl] in thf (or toluene) caused ligand exchange resulting in the formation of [(PPh(3))Pt(μ-PCy(2)){κ(2)P,O-μ-P(O)Cy(2)}Pt(PHCy(2))](Pt-Pt) (7) and [(PPh(3))Pt(μ-PCy(2)){κ(2)P,O-μ-P(O)Cy(2)}Pt(PPh(3))](Pt-Pt) (8). With [Au(PPh(3))OTf] (independently from the solvent) or with [Au(PPh(3))Cl] (only in dichloromethane), reaction with 1 gave [(PHCy(2))Pt(1)(μ-PCy(2)){κ(2)P,O-μ-P(O)Cy(2)}Pt(2){μ-Au(PPh(3))}(PHCy(2))]X(Pt-Pt) ([6]X, X = OTf, Cl) clusters in which the [Au(PPh(3))] moiety bridges the μP-Pt(2) bond. The [Ag(PPh(3))](+) electrophile attacks complex 1 selectively at the Pt(2)-μP bond to afford, at low T, the cationic cluster [(PHCy(2))Pt(1)(μ-PCy(2)){κ(2)P,O-μ-P(O)Cy(2)}Pt(2){μ-Ag(PPh(3))}(PHCy(2))](+)(Pt-Pt) (10(+)) in which the [Ag(PPh(3))](+) moiety bridges the μP-Pt(2) bond. Clusters analogous to 10(+), but without PPh(3) bonded to Ag, are obtained from reactions of 1 with AgOTf, AgBF(4), AgClO(4) and AgCl.