The kinetics of Ni-Cu-Mo alloy deposition has been investigated by means of steady-state polarization measurements. Strong interactions between the three discharging metals occur : nickel induces molybdenum deposition but its discharge is markedly inhibited by molybdenum. Copper deposition has a depolarizing effect on Ni-Mo discharge. Hydrogen evolution is associated with molybdenum deposition. The electrocrystallization process is dominated by the Ni-Mo codischarge kinetics.