We describe a large family of whom twelve members were shown to have a benign bone dysplasia known as "doughnut lesions of the skull". Its clinical features are pathological fractures and cranial lumps; its radiological features comprise doughnut cranial lesions, double cortical lines of the vertebral bodies ("bone in bone"), squaring of the metatarsal and metacarpal bones, osteopenia, and tubulation defects of the diaphyses of the long bones. We believe the disease to be transmitted as an autosomal dominant trait.