Kappler worked for George Morris for almost 25 years. Kappler was named Midwest Rider of the Year in 1987, 1988, 1989 and 1991. In 1989, he won the Lionel Guerrand-Hermes Trophy. He won the American Invitational and American Gold Cup three times each, and won the American Grand Prix Championship once. At the 2003 Pan American Games, Kappler won the team gold and individual silver riding Royal Kaliber. Also in 2003, Kappler was named the Equestrian of the Year by the
United States Equestrian Federation. In 2004, Kappler represented the United States at the
Olympic Games. Riding Royal Kaliber, he won team gold and individual silver. Kappler won the Budweiser Invitational in Tampa on his horse VDL Oranta in 2009. Kappler was a US Team Selector for the 2015 Pan American Games and the 2016 Summer Olympics. Kappler has been a USEF committee member. By 2018, Kappler decided to stop riding competitively and focus on training horses and riders. He often travels to teach clinics. ==Personal life==