Details of the synthesis, physical and spectroscopic characterization, and thermal decomposition of tris-(benzylthiolato)bismuth, (BnS)(3)Bi, Bn = CH2C6H5, are presented. Results from pyrolysis of (BnS)(3)Bi demonstrate that this compound is a convenient precursor to phase-pure, polycrystalline Bi2S3 with low carbon and hydrogen contamination under mild thermal conditions (ca. 275 degrees C). Flow-tube pyrolysis produces small (similar to 1 mu m) spherical particles, whereas sealed-tube pyrolysis produces 6-mu m diameter spherical particles composed of radiating acicular crystallites. Bi2S3 was characterized by X ray powder diffraction and scanning electron microscopy.