The photochromic behavior of viologens (V2+) and polyviologens (PV2+) was investigated using poly(N-vinyl pyrrolidone) (PVP) and poly(vinyl alcohol) (PVA) as matrices. In the PVP matrix the coloration rate of butylviologen bromide increases with decreasing humidity, but no influence of humidity on coloration rate was observed in the PVA matrix. The coloration rate in the PVA matrix follows a second-order plot while in the PVP matrix it does not. These results imply that, for the coloration process of viologens in polymer matrices, the effect of the matrix polymer as an electron donor must be considered. The fading rate of colored poly(butylviologen bromide) in PVP matrix increases remarkably with humidity. The fading reaction obeys a first-order relation at the very beginning and permits the determination of the rate constant. The fading rate increases with temperature with an activation energy of 13 kcal/mol. The fatigue of viologens and polyviologens was evaluated by the half-decay flash number. Polyviologens are more durable than their lower homologs.