The alveolar form of hydatid disease, caused by the larval stage of the cestode Echinococcus multilocularis, is virtually confined geographically to the northern hemisphere. It produces clinically malignant multivesicular infiltrating lesions most often in the liver, and is quite different from the usual cystic variety caused by E. granulosus. We present a case report of a patient with alveolar hydatid disease, whose treatment with mebendazole was brief due to side effects of alopecia and granulocytopenia; and review the features of this disease which, with increasing international migration, may be encountered more frequently in Australia.