The electrochemical behaviour of copper has been investigated in different cupric complex solutions by cyclic voltammetry. In pyridinic and picolinic solutions the reduction of cupric complex occurred in two stages leading to Cu( I) and Cu( 0), respectively. The electrodeposited copper is oxidized in two steps leading to Cu( I) and Cu( II) as in ammoniacal cupric complex solutions. In glycine, alanine, sulfamic acid and ethylenediamine solutions, the cuprous complex is an intermediate in the cupric complex reduction but it is not detected during the oxidation of the electrodeposited copper in these solutions. In EDTA and triethanolamine solutions, the cuprous complex is not observed. The rate of copper etching was determined in pyridinic and ammoniacal cupric solutions and was shown to be faster in ammoniacal cupric solutions than in the pyridinic solutions.