Fungi other than the dermatophytes can cause infections of the foot, toes and toenails that simulate classic "athlete's foot." Unless diagnosed culturally and morphologically by the clinical laboratory, treatment failures may occur. The saprophyte Hendersonula toruloidea as well as other fungi and yeasts reported to cause such infections have been shown to be clinically indistinguishable from classic dermatophytic "athlete's foot." The clinical and laboratory diagnosis of these types of foot infections caused by Hendersonula toruloidea are described. Specific transport media required for laboratory diagnosis and therapeutic alternatives are reviewed.