Abstract: A periscoping rear vision mirror assembly for use on motor vehicles to assist the driver to see over adjacent or following objects such as parked vans, trucks and the like, or over wide trailer loads. The mirror assembly has a vertically extendable mast mounted in front of the front windshield of a motor vehicle. The mast is extendable or retractable and a mirror is affixed near the top of the mast. When the mast is extended, the driver may look over an adjacent object, which would otherwise obscure his view, and observe oncoming traffic or other features.