Aspergillus fumigatus infection due to primary infection of the ethmoid sinus affected the brain and orbit of an otherwise healthy elderly woman. Primary nasal sinus infection may be a chronic process analogous to aspergilloma of the lung: it may, however, assume a locally invasive course and spread to the orbit or brain, as in the case described. This form of Aspergillus infection is rare in Europe but common in hot dry areas like the Sudan. The infection was probably contracted by our patient while on holiday in South Africa. Histological recognition of the condition is important in these unusual sites--many cases are clinically diagnosed as a tumour and undergo biopsy.