Migraine, a clinical syndrome of unknown etiology, is a common cause of a variety of visual disturbances. This review describes the visual alterations associated with migraine syndromes of particular interest to the ophthalmologist; acephalgic, ocular, and ophthalmoplegic. Several current theories of migraine pathophysiology are discussed. Migrainous episodes are common and must be differentiated from neurologic dysfunction due to ischemia, inflammation, seizure, and compression. The differentiating characteristics of these conditions as well as a diagnostic algorithm are presented. © 1989.