Rhenium(III) bromide reacts with pyridine, 3-chloro-pyridine, γ-picoline and benzimidazole to produce the rhenium(II) polymers [Re 3Br 6L 3] n. In contrast to this, pyrazine forms the unreduced adduct Re 3Br 9(pyz) 3. Prolonged reaction of rhenium(III) bromide with tri-n-propylphosphine and ethyldiphenylphosphine in refluxing methanol results in disruption of the trimer and reduction to metalmetal bonded dimers of the type Re 2Br 4L 4. Comparisons are made with the related reactions of rhenium(III) chloride.