Kathy Kusner got her start in the show ring by riding for local horse dealers in her native Virginia. While only 21 years old, she set the U.S Ladies High Jump record and was named "Horsewoman of the Year" before joining the United States Equestrian Team in 1961.

She was one of the first women ever selected to represent the United States Equestrian Team (USET) in Olympic competition. After riding at the 1964 Olympic Games in Tokyo and the 1968 Games in Mexico City, Kusner played an integral part in the USET's team Silver Medal victory in 1972 at Munich. She also won a team Gold Medal at the 1963 Pan American Games in Sao Paolo and a team Silver Medal at the 1967 Pan American Games in Winnipeg. Kusner was a two-time winner of the "Leading International Rider Award" at the National Horse Show and she earned international recognition in 1967 as the Ladies European Champion.

In 1968, after mounting a successful legal challenge, she became the first licensed woman jockey in the United States, riding races along the Eastern Seaboard and Canada. She went on to ride races throughout the world becoming the first licensed woman jockey in Mexico, Germany, Columbia, Chile, Peru, Panama, South Africa and Rhodesia. She was also the first woman to ride in the Maryland Hunt Cup, the world's toughest timber race.

Kusner established the organization, Horses in the Hood, which works with inner-city children in the Los Angeles area, introducing them to the wonderful world of the horse. Deeply involved with horses and how they touch others' lives, she conducted clinics and lectures throughout the United States and abroad.

She also worked as an expert witness and appraiser in connection with horse-related legal matters and was a course designer and television commentator for Grand Prix show jumping events. Several of her written articles were published in well-known equestrian journals.

On the horse Aberali, she did the riding for the long shots in the Disney movie "The Horse in the Grey Flannel Suit." While living in California, she has been involved with several productions companies, working on projects in Hollywood and "on location" in Banff, Canada.

A skilled pilot and an experienced scuba diver, Kusner was also a competitive runner, winning track and field events and road races. At the end of 1988, she had completed 33 marathons and 6 ultra-marathons, winning her division of the Colorado Pike's Peak Ultra-Marathon three times. She also won her division in almost every 10,000 meter road races in the Los Angeles area.