The cyclic voltammetric behavior of dioctadecylviologen (DV2+) films of different thickness self-assembled on Ag single crystal electrodes is described. The dependence of the voltammetric behavior upon the amount of viologen deposited on Ag and upon the scan rate is explained by the interplay of the dimerization steps yielding DV2+-DV+, DV+-DV+, DV+-DV0, and the two consecutive electron-transfer steps DV2+ + e(-) double left right arrow DV+ and DV+ + e(-) double left right arrow DV0.