Reaction of [Ag(CF3CO2)] with tetrahydrothiophene (tht) (2:1) in dichloromethane leads to the synthesis of [Ag4(CF3CO2)4(tht)2] (1), which further reacts with mesitylgold(I) ([Au(mes)]) (1:1) to afford [AuAg4(mes)(CF3CO2)4(tht)]n (3). Treatment of [Au(mes)] with [Ag(RCO2)] (R = CF3, CF2CF3) and tht (molar ratio 1:4:1 or 1:4:3) leads to the new Au/Ag systems [AuAg4(mes)(RCO2)4(tht)x]n (x = 1, R = CF3 (3), CF2CF3 (4); x = 3, R = CF3 (5), CF2CF3 (6)). The crystal structures of 3, 4, and 6 have been established by X-ray diffraction, all of them displaying Au···Ag interactions supported by mesityl ligands that bridge three metal centers in an unprecedented situation in transition metal chemistry. Additional Au−S−Ag and Ag−O−Ag (3 and 4) or Ag−S−Ag (6) bonds result in two-dimensional polymers that contain both Au···Ag and Ag···Ag contacts. Treatment of 3 with water (1:2) in dichloromethane leads to {[AuAg4(mes)(CF3CO2)4(tht)(H2O)]·H2O·CH2Cl2}n (7), whose crystal structure shows the partial break of the cyclic [...