The cationic Re(III) complexes trans-[Re(SCH2CH3)2(DIARS)2]+ and cis- and trans-[Re(SC6H5)2(DIARS)2]+, where DIARS = o-phenylenebis(dimethylarsine), have been synthesized and characterized. Preparation of these complexes proceeds from the Re(V) species [ReOCl3(PPh3)2] by reaction with excess thiol and diarsine at 100-degrees-C. The complexes have been characterized by FAB mass spectroscopy, visible-UV spectroscopy, elemental analysis, and cyclic voltammetry. X-ray crystal structure analyses of two of these complexes confirm that they have trans geometry. trans-[Re(SCH2CH3)2(DIARS)2]PF6, chemical formula ReAs4S2PF6C24H42, crystallizes in the orthorhombic space group Pbcn with Z = 4 and lattice parameters a = 13.505(2) angstrom, b = 12.490(5) angstrom, c = 21.703(4) angstrom and V = 3361(2) angstrom3. Important structural parameters are Re-S = 2.284(3) angstrom, Re-S-C = 119.50, and Re-As = 2.480(4) angstrom. trans-[Re(SC6H5)2(DIARS)2](C3H5O2).H2O, chemical formula ReAs4S2O3C35H49, crystallizes in the monoclinic space group P2(1)/c with Z = 4 and lattice parameters a = 17.099(5) angstrom, b = 17.515(3) angstrom, c = 13.545(5) angstrom, beta = 111.41(3)degrees, and V = 3777(2) angstrom3. Important structural parameters are Re-S = 2.298(5) angstrom, Re-S-C = 122(1)degrees, and Re-As = 2.50(1) angstrom. Electrochemical measurements show a reversible Re(III/II) redox couple at ca. -0.55 V for the trans complexes and ca. -0.52 V for the cis complex (both vs Ag/AgCl in TEAP/DMF). The properties of these Re(III)-DIARS complexes are compared to the properties of analogous complexes with chelating diphosphine ligands. Similar preparative reactions conducted at lower temperatures and shorter reflux times produce the Re(V) complexes [ReOCl(SR)2(DIARS)], R = CH2CH3 or C6H5. These complexes have also been characterized by FAB mass spectroscopy, visible-UV spectroscopy, and elemental analysis. An X-ray crystal structure of [ReOCl(SC6H5)2(DIARS)] shows that the thiolato ligands are cis. [ReOCl(SC6H5)2(DIARS)], chemical formula ReAs2ClS2OC22H26, crystallizes in the monoclinic space group C2/c with Z = 12 and lattice parameters a = 24.077(16) angstrom, b = 15.725(2) angstrom, c = 20.235(4) angstrom, beta = 99.88(4)degrees, and V = 7548(5) angstrom3.