A 39-year-old woman with no known systemic disease presented to the respiratory clinic for a routine chest radiography examination. She had no respiratory symptoms such as cough, sputum, dyspnea, or chest pain. Physical examination revealed bilaterally symmetrical lung sounds without crackles or wheezes. Chest radiography revealed diffuse osteosclerosis in the thoracic cage, bilateral clavicles, and scapulae, and cortical thickening of bilateral ribs (Fig. 1, arrows). Computed tomography of the chest at the mediastinum window (level 40 and width 350 Hounsfield units) revealed diffusely homogenous marked hyperdensities of all bony structures (Fig. 2). Dual-energy X-ray absorptiometry revealed a T-score of 5.6 (normal range, −1 to 1), obtained from L2 to L4 spines. Detailed anamnesis disclosed that her father had had a history of bilateral hip fractures and been told that he had dense bones on radiographic examination. A diagnosis of Albers-Schönberg disease or autosomal dominant osteopetrosis was made. She was advised to avoid strenuous exercise for prevention of fracture and she remained asymptomatic with regular follow-up at the clinic.