We review the use of topical tretinoin (all-trans-retinoic acid) in the treatment of aging skin. We have found topical tretinoin capable of improving aged-appearing skin in both a double-blind, vehicle-controlled trial and our clinic patients. The most impressive improvement occurs after application of tretinoin 0.1% cream for 8 to 12 months. Side effects have been limited to a mild, transient, and clinically insignificant burning sensation in the eyes and mild irritation of tretinoin-exposed skin.