An electro-oculogram (EOG) was derived from potentials recorded from electrodes placed above and below the eye during voluntary vertical eye movements. Concurrent measurement of the amplitude of eye blink potentials recorded from the same electrodes produced curves which were highly correlated with the EOG measured from stereotyped eye movements. Recordings from a patient with a missing globe, owing to trauma, revealed eye movement and blink responses only from the intact side. A patient with no light perception showed blink responses which were less variable than responses measured during attempts voluntarily to move the eyes vertically in 600 excursions. An EOG calculated by measurement of eye blink potentials may be possible in clinical situations where traditional electro-oculography techniques are not feasible.