Twenty patients with nevus of Ota have been treated with the argon laser, Q-switched yttrium-aluminum-garnet (YAG) laser, or a combination of both lasers. The argon laser was originally used from 1975 to 1993 and has now been replaced by the Q-switched YAG laser. The Q-switched YAG laser mechanism of action is selective photothermolysis in which the pulse width of the laser beam is very short, thus allowing the melanocyte chromophore target to dissipate its heat without burning adjacent normal tissue. Satisfactory fading without skin scar or texture change was observed in 10 patients in this series who had completed treatment; treatment is in progress in the remaining 10 patients. Six patients who were initially treated with argon and then subsequently were treated with Q-switched YAG laser demonstrated improved results.