Career
Initially competing in showjumping Jefferis switched to Eventing in 1990 and had immediate success, being part of the Gold medal team at the World Equestrian Games in Stockholm riding Enterprise. Jefferis purchased Bounce in 1994 and rode the horse for the remainder of his international career. Their last event was at the 2000 Summer Olympics in Sydney but they did not complete the event.
Unlike the majority of his team-mates, such as Mark Todd, Andrew Nicholson and Blyth Tait, who based themselves in England, Jefferis remained in New Zealand throughout his career.
After retiring in 2000 he has concentrated on producing and training horses. In August 2008, Jefferis announced he was making a comeback to top-level eventing, and would aim for the 2012 London Olympics.