The reaction of [K][ReH6(PPh3)2] with IrCl(CO)(PPh3)2 leads to formation of the complex (CO)(PPh3)2-Re(mu-H)3IrH(PPh3)2 (1) in 36% yield. Its structure has been established by variable temperature H-1 and P-31 NMR and X-ray diffraction; it consists of two distorted octahedra sharing a face containing three bridging hydrides. The iridium atom is bonded to a terminal hydride and to two phosphine ligands. The position of the hydrides has been calculated using the program HYDEX. Crystallographic data for 1 : monoclinic C2h5-P2(1)/n, a = 14.818(3) angstrom, b = 20.750(2) angstrom, c = 21.693(3) angstrom; beta = 96.29(2)-degrees, V = 6629 (2) angstrom3, Z = 4; R= 0.0374, R(W) = 0.0435 for 3845 observations and 406 variable parameters. The compound 1 reacts with HBF4.OMe2 to give [(CO)(PPh3)2HRe-(mu-H)3IrH(PPh3)2][BF4] which has been isolated as its tetraphenylborate salt and characterized by variable temperature H-1 and P-31 NMR spectroscopy. Protonation has induced the formation of rhenium-terminal hydride bond.