In eight patients with monostotic fibrous dysplasia in the femoral neck, the lesion was virtually limited to the neck region without any extension into the shaft. In one patient with symptoms of 40 years' duration and another with a recurrent lesion, there was a deformity in the neck of the femur. A pathologic fracture, including a minor one, was identified in two patients. Roentgenographically, the lesion should be distinguished from various entities producing a localized central region of rarefaction in the proximal femur. The histologic features of fibrous dysplasia are characteristically diagnostic. Six of the eight patients were successfully treated by curettage and bone graft. There was no evidence of malignant transformation.