The most common causes of internuclear ophthalmoplegia (INO) are multiple sclerosis and vascular disease of the brain stem. Rarer causes are tumor, Arnold-Chiari malformation, and syphilis. Myasthenia gravis has, on occasion, presented with ocular abnormalities indistinguishable from INO. A case is described of bilateral INO of brief duration following head trauma. There were no other brain-stem abnormalities. This brings to 11 the number of reported patients in whom head trauma precipitated this abnormality.