The small-signal impedance response of electrochemical cells in which the ionic transport obeys the Nemst-Planck and Poisson equations is interpreted by means of the network method. The method is general and extremely efficient; it permits treatment of multi-ion systems and imposition of conditions on both the electric potential and the electric current density through the cell. The network model of some representative electrochemical cells, including non-faradaic processes and interfacial kinetics described by a Butler-Volmer type equation, has been obtained, and the electrochemical impedance of these systems has been simulated with the aid of the PSPICE program.