Howard Simpson grew up fox hunting and served as Master of the Foxhounds (MFH) for the Mill Creek Hunt in Illinois. He was a member of the U.S. Air Force from 1969 until 1972 during which he was a paramedic and member of the flight surgeons office during his tour in Vietnam.

Simpson married Martha Smith (now Martha Smith Simpson) in 1984 and the next year the pair, along with Smith’s sister, Linda Buonanno, hosted the first American Continental Young Riders Championship at their Tempel Farms in Wadsworth, Illinois. In 1988, the competition would become the North American Young Rider Championships (NAYRC) which would evolve into the NAJYRC and in 2018 the NAYC. In 1997, Simpson took over as the sole organizer of the NAJYRC and provided much needed financial support for the program. He would serve as the Director of the NAJYRC for more than 20 years and Tempel Farms would host the championships in 1985, 1988, 1990, 1991, 1993, 1994, 1995, 1996, 1997, 1999, 2001, 2002, and 2004.

In addition to his work with young riders, Simpson was involved in site selection for important events. In December 1996, the United States Equestrian Team (USET) asked the American Horse Show Association (now USEF) to investigate a site for the first four-star in North America. Simpson was selected along with then U.S. Chef d’ Equipe Captain Mark Phillips to investigate potential sites. The pair eventually decided upon the Kentucky Three-Day Event to become a CCI4*. Simpson used that experience as Chairman of the task force to select the second CCI4* in North America, which will eventually be held at Fair Hill International.

In the early 2000s Simpson was a member of the USEA Board of Governors and served as Vice President of Communications. He was on the former USET Board of Directors and continues to serve on USEF committees including the USEF Board of Directors. He is currently a member of the Rebecca Broussard International Developing Rider Grant Selection Committee.

In 1997 Simpson was honored with the Wofford Cup, an award that is chosen each year by past recipients to recognize those that have given back to the sport of eventing, as well as a Governor's Cup from the USEA. In 2002 Simpson received the Towerheads’ Distinguished Service to the Industry Award, and in 2004 he was the winner of the USEF Perpetual Sportsmanship Award. Given in memory of Walter Bourchier Devereux, III, the Perpetual Sportsmanship Award honors the horseman or horsewoman who “exemplifies the ideal of good sportsmanship through commitment, dedication, and service to USEF throughout his or her career.” Simpson also received the Sallie Bush Wheeler Award in 2011 and 2015 and the Pegasus Medal of Honor in 2015. Most recently, Simpson was chosen to receive the USEA President’s Lifetime Achievement Award in 2016.

In 2004 the USEF started giving a new award annually at the NAJYRC. The Howard B. Simpson High Five Trophy is awarded to a volunteer who best exemplifies Simpson’s spirit of volunteering, dedication, and commitment to the Championships. Simpson was the inaugural recipient of the award.