Invasive aspergillosis is generally a life-threatening invasive opportunistic mycosis affecting principally the upper and lower respiratory tract. Therapeutic response rates vary considerably from one host group to another with particularly high mortality rates in bone marrow transplant, liver transplant and patients with aplastic anaemia or AIDS. Only two drugs are useful for therapy, amphotericin and itraconazole. Recent advances in the formulation of amphoterin B (AmBisome and Amphocil) have resulted in intravenous preparations with lower toxicity, particularly nephrotoxicity, but it has yet to be shown that they have an increased therapeutic index for the treatment of invasive aspergillosis. Itraconazole can only be used orally and in some particularly high-risk or critically ill patients adequate serum concentrations cannot be achieved. The addition of flucytosine or rifampicin to amphotericin B therapy has, at best, only a marginal benefit. Surgery is essential for some manifestations of invasive aspergillosis. This article reviews therapeutic strategies including criteria for initiation of therapy, combination and sequential therapy, duration of therapy and secondary prophylaxis and indications for surgery in invasive aspergillosis.