We describe a family in which cutaneous malignant melanoma or cerebral astrocytoma, or both, developed in eight members over three generations. Other malignancies also occurred with a lesser frequency. In two patients with both malignant melanoma and astrocytoma, the brain tumor followed the diagnosis of melanoma by a period of 2 and 10 years and was the primary cause of morbidity and mortality. The findings in this family may represent a newly described genetic disorder.