Twenty-three patients with 30 nails affected by dermato-phyte infection were treated with a topical application of 1% bifonazole (Bayer) with 40% urea. Direct examination for fungi and culture on Sabouraud's medium were both positive for dermatophytes in all cases before treatment. Clinical and mycological examinations were carried out weekly until normal nail growth occurred. At the end of week 1 after treatment most direct examinations (66%) for fungal mycelium gave negative results and all cultures were negative. By week 4 of treatment 30% of nails detached. Detachment did not occur in 2 cases. Reinfection was observed in only 3 cases (10%). The bifonazole/urea combination is a very effective treatment in onychomycosis and avoids the systemic toxicities of other drugs.