A Trichophyton mentagrophytes infection of guinea pigs induced by an occlusive procedure is described. The method of evaluation permits comparison of efficacy of antifungal agents which are not tested simultaneously. Activity was demonstrated following topical application of clotrimazole, miconazole, tolnaftate or griseofulvin and oral administration of griseofulvin. Oral ketoconazole had little effect in this dermatophyte model.