OBJECTIVE: To review the role of itraconazole as oral therapy for the major infections caused by Aspergillus spp.: allergic bronchopulmonary aspergillosis, aspergilloma, and invasive aspergillosis. DATA SOURCES: A MEDLINE search of articles published in the English language between 1986 and 1993 was used to identify relevant citations, including review articles. In addition, a search of the published abstracts of the past two Interscience Conferences on Antimicrobial Agents and Chemotherapy (ICAAC) was performed. STUDY SELECTION: Clinical trials that evaluated itraconazole therapy in either allergic bronchopulmonary aspergillosis, aspergilloma, or invasive aspergillosis were critically reviewed. Trials were evaluated based upon entry criteria for the diagnosis of each type of aspergillosis, risk factors for the development of aspergillosis (neutropenia, transplant recipient, hematologic malignancy), prior antifungal chemotherapy, and dose and duration of itraconazole therapy. DATA SYNTHESIS: Overall, the clinical trials of itraconazole therapy for aspergillosis are limited and of variable quality. In the treatment of allergic bronchopulmonary aspergillosis, itraconazole has been reported to prompt a reduction in corticosteroid dosage in selected patients. There have been no controlled trials of itraconazole as treatment for aspergilloma, but data from several open-label trials suggest that this agent may be of clinical benefit in aspergilloma, primarily as an alternative to surgery. The use of itraconazole for invasive aspergillosis has been evaluated in several trials, most often in patients who were intolerant to amphotericin B treatment. Response to oral itraconazole has generally been promising. CONCLUSIONS: Although itraconazole offers promise for oral therapy against infections caused by Aspergillus spp., it should not presently be regarded as primary therapy for any of these diseases. Amphotericin B, in doses ranging from 1 to 1.5 mg/kg to a total dose of 1.5–4.0 g, should remain the treatment of choice in both aspergilloma and invasive aspergillosis. Itraconazole use should be restricted to patients who experience severe toxicity with amphotericin B therapy. Corticosteroids continue to be first-line therapy for allergic bronchopulmonary aspergillosis, with the use of itraconazole reserved for those patients who would benefit from a reduction in corticosteroid dose.