The onset of periorbital xanthogranuloma in adults is rare and may be accompanied by haematological abnormalities and malignancy. The appearance of the eyelid lesions is virtually diagnostic, producing readily recognisable diffuse, yellow plaques, and affected patients should be investigated and reviewed regularly for systemic disease. Three cases are described, in which periorbital cutaneous plaques were associated with abnormal tissues in the superior part of the orbit; these abnormal tissues caused displacement or restricted movement of the globe or upper eyelid. The possibility that two cases represent a necrobiotic type of xanthogranuloma is presented. Nine years after the onset of xanthogranuloma one patient developed non-Hodgkin's lymphoma. A multiple-drug regimen of systemic chemotherapy, given for lymphoma, caused a marked clinical reduction in the periorbital xanthogranuloma.