Impressive (15 April 1968 – 20 March 1995) was born an Appendix American Quarter Horse, who earned his full AQHA registration in 1971. He was the 1974 World Champion Open Aged halter stallion, the first such World Champion in his breed, despite carrying only 48 halter points in total. He is famous for his highly successful progeny, having sired 2,250 foals. Nearly thirty of his offspring went on to be World Champions themselves.

Impressive is also notorious as the primary source of the widespread genetic disease known as Hyperkalemic periodic paralysis (HYPP).

In his showing days, Impressive changed hands a number of times, perhaps his most famous owner being Dean Landers, who also owned the famous halter stallions Two Eyed Jack, Coy's Bonanza, and Sonny Dee Bar. Although Impressive raced for a short time after Landers sold him to Fennel Brown, he was quickly excluded from any performance discipline due to pedal osteitis, leaving halter as his only choice. His groundbreaking 1974 World Championship soon cemented his role in that discipline. Each time Impressive was resold, his price rose quickly; at one point, an offer of $300,000 for him was refused by Brown, who said "ain't nobody in this world got enough money to buy this horse."