Efforts to account for observed trace metal concentrations in anoxic marine waters have had only limited success due in part to the lack of knowledge of the identity and concentration of the organic sulfur compounds that are present. There have been no previous attempts to measure trace metals concentrations simultaneously with the inorganic and organic sulfur species in marine waters. In addition to the conventional methods for the determination of the inorganic species, we are developing methods for the determination of the biogenic thiols and disulfides using an HPLC separation coupled to selective electrochemical detection. Preliminary results on the analysis from anoxic sediment pore waters will be presented. Current thermodynamic models describing the solubility of sulfide minerals in anoxic marine waters will be refined to include complexation of chalcophile trace metals by organic thiols.