Two brothers with the X-linked disorder, dyskeratosis congenita, are described. They showed the dermatologic triad of reticular hyperpigmentation, dystrophic nails, and leukoplakia oris as well as the other major feature of this disorder, aplastic anemia. Less common features observed included prenatal and postnatal growth retardation, mental retardation, elevated immunoglobulin levels, and gastrointestinal hemorrhage from mucosal ulceration. Previously unreported findings were intracranial calcifications and nutmeg-like cirrhotic changes of the liver. These brothers demonstrated that skeletal changes and bony fragility may predate anemia or steroid therapy. Although a DNA repair defect is postulated as a possible primary defect, cytogenetic studies revealed no evidence of increased chromosomal breakage.