Melasma (a term derived from the Greek word "melas" meaning black) is an acquired blotchy, irregularly patterned, brown or sometimes gray brown hypermelanosis of the face and occasionally the neck. Its etiology is poorly understood but mainly related to sunlight and genetic predisposition. Melasma seems to be more frequent in darker skinned people, especially women. Its treatment is always difficult and the condition usually relapses. The treatment with pidobenzone 4% (K5 lipogel), twice per day for 16 weeks has proved to be safe and effective. Pidobenzone 4% lipogel, according to the present study, seems also to represent a useful, reliable, and safe treatment of the different types of melasma.