Some of today's competition ponies have become specialized by type. For example, in the United States, the Shetland is either Classic or Modern. The Classic is more muscular, with the breed's trademark small head. In its rules, the AHSA defines its height limits for ponies as the universal size of 14.2 hands. To clarify pony status for show purposes, AHSA requires certain officials, including licensed veterinarians, to measure entrants.
Ponies receive their own measurement cards as records.
AHSA divides pony hunters into small, medium, or large categories, with each size dictating the fence heights and distances between fences. Ponies have also been crossed with horse breeds to produce winning pony hunters. The typical infusion of Thoroughbred or Arabian blood can result in a more elegant show pony bred for jumping talent. The larger crossbreds show a flatter movement and longer stride. Ponies often compete in show driving classes, and in cross-country they can keep up with horses.