On December 15, 1999, the National Institute for Occupational Safety and Health (NIOSH) received a request from employees of the United States Virgin Islands Department of Health, Saint Croix. Employees working at the Charles Harwood Complex (CHC) believed that their headaches, coughing, rash, itching, infections, respiratory problems, and eye irritations, were related to working in this building. On May 16, and 17th NIOSH investigators conducted a site visit at the CHC. On May 16, 2000, NIOSH investigators conducted a walk-through inspection of the entire CHC. On May 16 and 17, 2000, air sampling was conducted for culturable fungi using an Anderson single-stage cascade impactor with malt extract agar, fungal spores using Air-O-Cell (trademark) media and mixed cellulose ester filters, and endotoxin using poly-vinyl chloride filters. Bulk samples were collected of materials with suspect fungal colonies from various areas of the CHC. Carbon dioxide (CO2), temperature, and relative humidity (RH) measurements were collected, and the condition of the air-conditioning systems was determined. Areas suspected of water damage (exterior walls, floors, and near windows) were probed with a moisture meter to qualitatively assess residual amounts of water. Total fungal concentrations were higher outdoors than indoors for a majority of the air samples collected. However, some indoor air samples revealed a larger percentage of Aspergillus and/or Penicillium species than outdoor air samples, suggesting the presence of fungal reservoirs. Stachybotrys chartarum, Cladosporium, and A. sydowii were the predominant fungal species identified in the ceiling tile bulk samples collected in the unoccupied 3rd floor, executive wing, which indicates past or present microbial contamination. All CO2 concentrations were below 800 parts per million (ppm), suggesting that the two story building was receiving sufficient amounts of outside air. Temperature and RH levels ranged from 72 degrees-F to 84 degrees-F, and 33% to 74%, respectively. Some temperatures were beyond the thermal comfort parameters recommended by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). NIOSH investigators conclude that there was a potential for airborne fungal exposures in this complex resulting from moisture incursion. The building revealed evidence of localized patches of microbiological contamination and water-damaged materials. Air sampling in some indoor areas indicated a larger percentage of Aspergillus and/or Penicillium species than outdoor air samples, which suggests the presence of fungal reservoirs. Additionally, bulk samples of ceiling tiles revealed the presence of Stachybotrys chartarum. Continued delays in roof reconstruction and renovation of structurally damaged portions and closed interior wings could result in a progressive increase of fungal colonization. Recommendations are provided to assist in eliminating the wet conditions conducive to microbial growth and to generally improve the indoor environment.