Corticosteroid therapy is of great value in many types of eye disease. The indications are briefly discussed, together with the choice of agent and mode of administration. The dangers of steroids are now widely recognized, and the complications are discussed, particularly cataract and glaucoma. Reference is also made to optic neuritis and thyroid ophthalmopathy, where the role of steroids is uncertain. Particular stress is laid on the need to keep steroid dosage as low as possible, so as to avoid systemic side effects. There are unfortunately many situations where treatment of doubtful efficacy has produced severe side effects. Despite the overall benefit of steroids in ophthalmology, there is a pressing need to find alternative treatment for a variety of blinding disorders.