A total of 40 coal miners, 35 with culturally proven mycotic infections of the feet and 5 with similarly proven infections of toenails due to Hendersonula toruloidea, Scytalidium hyalinum and dermatophytes, were treated with 1% cream of either isoconazole nitrate (Travogen) or clotrimazole (Canestan) for 4 weeks. The clinical cure rates for the isoconazole-treated group for itching, inflammation, scaling and maceration in the cases of foot infections were 89, 88, 83 and 83% respectively. For the clotrimazole-treated group, the cure rates were 76, 71, 82 and 80% respectively, for the similar symptoms. Toe web was the commonest site of infection and also most easily treated with either clotrimazole or isoconazole. The clinical and mycological cure rates 6 weeks after treatment were 80% for the isoconazole-treated group and 70% for the clotrimazole-treated group but the difference was not statistically significant (P > 0.01). None of the cases of toenail infection could be cured by treatment with either of the two drugs.