The recording of vestibular nystagmus by electronystagmography and other methods is becoming a common practice in clini-ca1 8 ,19 and experimental/" evaluation of the vestibular system. With adequate recording equipment, displacement of the pen is approximately proportional to angular displacement of the eyes, and paper speed determines the time base of the recordings. Several measurements of such records have been of primary interest: 1) duration of nystagmus, 2) total angular displacement of the eyes in the slow phase direction within some time interval, 3) angular velocity of the eyes in the slow phase direction of a number of points in time during the course of the response, and 4) number of nystagmus beats.With the exception of duration, which requires a decision only about nystagmus termination, these different measures of nystagmus can be very time-consuming when done manually. The present report describes two devices, one similar to a trace reader described by Benson and Stuart" and another complementary device, which facilitate measurement of nystagmus records and also facilitate the digital and analog presentation of the analyzed nystagmus data.