Copper can be won with low power consumption from an acidified cuprous sulphate solution containing organic nitriles in a one electron process to give smooth non-dendritic copper cathodes and cupric sulphate at the inert anode. A diaphragm is necessary if cupric sulphate is allowed to concentrate in the cell. In the presence of an organic nitrile in water, cuprous sulphate is stable and cupric sulphate oxidises copper to cuprous sulphate. A scheme for refining crude copper to cathode copper without casting anodes is proposed. Various inert anode materials are compared