Ophthalmopathy develops in about 30% of patients who have Graves' disease. The pathogenesis, like that of the hyperthyroidism, is probably autoimmune in nature. The eye manifestations are diverse and include lid lag, soft tissue swelling, proptosis, corneal damage, diplopia, and optic neuropathy. The natural history is benign in 90% of patients, with gradual improvement over time. Therapeutic options include corticosteroid therapy, radiation, and surgical treatment. The last is usually the therapy of choice for severe or disfiguring ophthalmopathy.