In New York, for instance, it's a regular part of the Empire State Games. At the 1994 World Ski-O Championships in Italy, Laurie Collinsworth's 26th place finish ranks as the best showing by an American in any international orienteering competition. While ski-o offers plenty of opportunities for top flight competitors, it's a perfect family sport as well. Technically it's easier than regular orienteering because the flags are all on the trails. What's most important is the ability to ski fast.
Participants can compete against the clock and each other or ski the courses recreationally.
Skate skiing can give you an advantage in some cases but on steep sections and with narrow trails you need the classical. Ski-o also requires no special equipment, aside from a compass. The compass isn't so much for fine navigation as to ensure you're not making any gross directional errors. Some orienteers place their map in a special chest mounted holder, but most keep it in a plastic bag pinned to their jacket. What makes the most difference is what your head and your body have.