Thirty-two Ru(porp)L-2 complexes have been synthesized, where porp = the dianion of meso-tetramesitylporphyrin (TMP) or meso-tetrakis(4-methylphenyl)porphyrin (H2T-pMe-PP), and L = a thiol, a sulfide, a disulfide, or a trisulfide. Species studied were with RSH [R = Me, Et, Pr-n, Pr-i, Bu-t, Bn (benzyl), and Ph], RSR (R = Me, Bn), RSSR (R = Me, Et, Pr-n, Bn) and (MeSSBu)-Bu-t, and RSSSR (R = Me, Bn). All the species except two, which were the isolated Ru(T-pMe-PP)((BuSH)-Bu-t)(2) and Ru(TMP)(MeSSMe)(2), were characterized in situ. The disulfide complex was characterized by X-ray analysis. H-1 NMR data for the coordinated thiols are the first reported within metalloporphyrin systems, and are especially informative because of the upfield shifts of the axial sulfur-containing ligands due to the porphyrin pi-ring current effect, which is also present in the di- and trisulfide species. The disulfide in the solid state structure of Ru(TMP)(MeSSMe)(2) is eta(1)(end-on) coordinated, the first example of such bonding in a nontethered, acyclic dialkyl disulfide; H-1-H-1 EXSY NMR data in solution show that the species undergoes 1,2-S-metallotropic shifts. Stepwise formation of the bis(disulfide) complex from Ru(TMP)(MeCN)(2) in solution occurs with a cooperativity effect, resembling behavior of Fe-II-porphyrin systems where crystal field effects dominate, but ligand trans-effects are more likely in the Ru system. The eta(1)(end-on) coordination mode is also favored for the trisulfide ligand. Discussed also are the remarkable linear correlations that exist between the ring-current shielding shifts for the axial ligand C-1 protons of Ru(porp)(RSxR)(2) and x (the number of S atoms). The Introduction briefly reviews literature on Ru- and Fe porphyrins (including heme proteins) with sulfur-containing ligands or substrates, and relationships between our findings and this literature are discussed throughout the paper.