Cuprous chloride-assisted aromatic bromodeiodination was investigated as a regioselective no-carrier-added labelling technique. Using 77Br-, CuCl and simple iodinated aromatic substrates in DMSO, radiochemical yields ranged from 60 to 90% after 30 min at 135 degrees C. The methodology described here holds potential for the convenient labelling of radiopharmaceuticals with 75Br, 76Br or 77Br.