The aim of this protocol is to use modern methods in molecular and cell biology and immunology to elucidate the immunopathogenesis of fungal disease in humans. A better understanding of primary immunodeficiency and identification of fungal and host risk factors for fungal infection may provide new insights into pathogenesis and identify targets for development of novel therapies. Enrolled subjects may be followed for up to 10 years to undergo additional clinical evaluation and sampling. Follow-up may occur every 6 months or more frequently depending on clinical course, the underlying risk factor(s), and the type of fungal infection. Under some circumstances, standard medical treatment will be provided for a fungal infection or immune deficiency.