Cyclic voltammetry and controlled-potential electrolysis have been employed to investigate the electrochemical reduction of 3,3'-dibromo-, 5,5'-dibromo-, and 5,5'-dichloro-2,2'-bithiophenes at carbon cathodes in dimethylformamide containing tetramethylammonium perchlorate. Reduction of 5,5'-dibromo- and 5,5'-dichloro-2,2'-bithiophene gives rise to three cyclic voltammetric waves that correspond to the reductive cleavage of the carbon-bromine bonds and to the reduction of 2,2'-bithiophene. Cyclic voltammograms for the reduction of 3,3'-dibromo-2,2'-bithiophene exhibit two cathodic waves attributed to the scission of the carbon-bromine bonds and to reduction of 2,2'-bithiophene. Bulk electrolyses of dihalo-2,2'-bithiophene at potentials for different stages of reduction lead to products that are consistent with expectations based on cyclic voltammetry. Controlled potential catalytic reductions of 3,3'-dibromo-, 5,5'-dibromo-, and 5,5'-dichloro-2,2'-bithiophene by electrogenerated nickel(I) salen afford the corresponding monohalo-2,2'-bithiophene in high yield (74-83%) through a one-electron process.