The reactivity of the metalloligand [Pt 2 (μ-S) 2 (PPh 3 ) 4 ] towards a variety of indium(III) substrates has been explored. Reaction with excess In(NO 3 ) 3 and halide (KBr or NaI) gave the four-coordinate adducts [Pt 2 (μ-S) 2 (PPh 3 ) 4 InX 2 ] + [InX 4 ] − (X=Br, I). An X-ray structure determination on the iodo complex revealed a slightly distorted tetrahedral coordination geometry at indium. In contrast, reaction of [Pt 2 (μ-S) 2 (PPh 3 ) 4 ] with indium(III) chloride was more complex; the ion [Pt 2 (μ-S) 2 (PPh 3 ) 4 InCl 2 ] + was initially observed in solution (using ESI mass spectrometry), and isolated as its BPh 4 − salt. Analysis of [Pt 2 (μ-S) 2 (PPh 3 ) 4 InCl 2 ] + [BPh 4 ] − by ESI MS showed the parent cation when analysed in MeCN solution. However in solutions containing methanol, partial solvolysis occurred to give the di-indium species [{Pt 2 (μ-S) 2 (PPh 3 ) 4 InCl(OMe)} 2 ] 2+ (proposed to contain an In 2 (μ-OMe) 2 unit with five-coordinate indium) and its fragment ion [Pt 2 (μ-S) 2 (PPh 3 ) 4 InCl(OMe)] + . Reaction of [Pt 2 (μ-S) 2 (PPh 3 ) 4 ] with InCl 3 ·3H 2 O, 8-hydroxyquinoline (HQ) and trimethylamine in methanol gave the adduct [Pt 2 (μ-S) 2 (PPh 3 ) 4 InQ 2 ] + , isolated as its PF 6 − salt. The same cationic complex is formed when [Pt 2 (μ-S) 2 (PPh 3 ) 4 ] is reacted with InQ 3 in methanol, but in this case the product is contaminated with the mononuclear complex [(Ph 3 P) 2 PtQ] + formed by disintegration of the trinuclear complex [Pt 2 (μ-S) 2 (PPh 3 ) 4 InQ 2 ] + with byproduct Q − . [(Ph 3 P) 2 PtQ] + BPh 4 − was independently prepared from cis-[PtCl 2 (PPh 3 ) 2 ] and HQ/Me 3 N, and is the first example of a platinum 8-hydroxyquinolinate complex containing phosphine ligands.