This study employed video-based simulation to examine the effect of in-vehicle navigation information systems upon driver attention. Guidance in the form of a direction-indicating arrow, accompanied by an audible signal, required less time looking at displays, and led to better anticipation of direction changes than did an area map, strip map, or position-indicating display. The benefits of guidance disappeared when the position information was added. No significant differences were found in response to highway-traffic conditions, an outcome attributed to the small time required in gaining navigational information.