While exposure/symptom relationships are relatively well-defined for pollen allergens, such relationships have not been clearly established for airborne fungus spores due to a lack of clearly defined seasonal patterns, prevalence of world-wide cosmopolitan fungi, and serious problems with sampling and identification. Ascospores and basidiospores have been least studied with respect to aerobiology, although both are clearly allergenic. Preliminary data on allergenicity and diurnal and seasonal prevalence patterns for selected ascospore and basidiospore types are presented.