Invasive fungal sinusitis can develop in immunosuppressed patients. A more complex problem is immunosuppressed patients who have undergone bone marrow transplantation. For a prolonged period, they are both neutropenic and thrombocytopenic. Survival in these patients is poor, and the role for extensive surgical intervention for sinus disease has to be weighed against the risk and the potential that this is a systemic disease. Between January 1983 and June 1993, 29 bone marrow transplant recipients with documented invasive fungal infections of the sinuses and paranasal tissues required surgical intervention. This represents 1.7% of the total 1692 bone marrow transplants performed. There were 22 allogeneic, 6 autologous, and 3 unrelated donor transplants, with two patients receiving two separate grafts. Underlying diseases included 24 hematologic malignancies and 5 other disorders, including 1 aplastic anemia and 1 solid tumor. The mortality rate from the initial fungal infection was 62%. Twenty-seven percent resolved the initial infections but subsequently died of other causes. All patients received medical management, such as amphotericin, rifampin, and colony- stimulating factors, in addition to surgical intervention. Surgical management ranged from minimally invasive procedures to extensive resections including medial maxillectomies. Sixty-one percent of the patients who died of the initial infection had undergone extensive surgical procedures versus 55% of those who resolved the infection. Recovery of neutrophil counts was required to clear the infection but did not necessarily predict a good outcome because 50% of those who died of the infection had experienced neutrophil recovery. White blood cell counts at the time of surgery were not significantly different between the two groups. Prognosis was poor when cranial and orbital involvement and/or bony erosion occurred.