Fungal spores are well known allergens and represent an important exposure risk for sensitive patients. In recent years there have been increasing concerns about the concentration of airborne fungi in indoor door environments. Previous studies of indoor fungi in the Tulsa area focused specifically on culturable fungi; however, culturable fungi are only a portion of total air spora. Some fungi are unable to grow on the culture media used, while other fungi are obligate plant pathogens and are only able to grow on the plant host. In addition, other airborne fungal spores may lose viability but still retain allergenic properties. As a result the use of cultural techniques does not assess the actual exposure risk for sensitive individuals. The current study determined the concentrations of total fungal spores collected at 12 homes or offices sampled during September, November, and February. The buildings sampled were houses or offices of patients diagnosed with mold allergies, although none of the sites had visible fungal contamination. Air samples were collected for 10 minutes indoors and 5 minutes outdoors with Burkard Personal Samplers. Slides were made permanent by mounting a coverslip with glycerin-jelly mounting medium and were analyzed microscopically at 1000X. Spore counts were converted into concentrations and expressed as spores/m³. A total of 124 indoor samples and 30 outdoor samples were collected. Mean indoor concentrations were approximately 1,250 spores/m³ in September, 1,500 spores/m³ in November, and 770 spores/m³ in February. As expected, outdoor levels were much greater with the mean levels approximately 25,000 spores/m³, 5,700 spores/m³, and 1,250 spores/m³, in September, November, and February respectively. Outdoor levels were dominated by Cladosporium conidia, basidiospores, and ascospores; while indoors, Penicillium/Aspergillus type spores, which are well known allergens, were the dominant spore type identified with Cladosporium conidia second. Although the seasonal decrease occurred both indoors and outdoors, the outdoor levels decreased 95% from September to February. By contrast, the indoor levels only decreased by approximately 50%. These results explain why exposure to fungal allergens can remain a problem for sensitive individuals year round.