A simple efficient, stereoselective and regioselective method for the synthesis of β- chlorohydrins, β-bromohydrins, and β-iodohydrins by the direct opening of 1, 2-epoxides with the corresponding ammonium halide in acetonitrile, in the presence of metal salts, is described. This new method appears to be of general use and competitive with the other methods previously reported.