According to the results obtained in a recent clinical trial over a four-year period retinoic acid represents the most effective single agent available for the topical management of acne vulgaris. Retinoic acid yields impressive therapeutic results not only in patients with manifest acne, but, provided it is applied early enough, it is also effective in preventing the severe inflammatory manifestations of this disease. In medium to severe cases of inflammatory acne, topical retinoic acid therapy should be combined with a low-dose, long-term systemic tetracycline regimen. The course of treatment may extend over months or years, depending on the severity of the condition. Particularly patients in the acne-prone age group are candidates for long-term therapy. Retinoic acid therapy, alone or in combination with tetracyclines, proved far superior to conventional regimens with respect to the effective treatment and prophylaxis of acne.