The National Association for Stock Car Auto Racing (NASCAR) is a family-owned and operated business venture that sanctions and governs multiple auto-racing sports events. Bill France, Sr. founded the company in 1948 and his grandson Brian France became their CEO in 2003 NASCAR is motorsport's preeminent stock-car racing organization. The three largest racing-series sanctioned by this company are the Sprint Cup Series, the Xfinity Series, and the Camping World Truck Series. The company also oversees NASCAR Local Racing, the Whelen Modified Tour, the Whelen All-American Series, and the NASCAR iRacing.com Series. NASCAR sanctions over 1,500 races at over 100 tracks in 39 of the 50 US states as well as in Canada. NASCAR has presented exhibition races at the Suzuka and Motegi circuits in Japan, the Autódromo Hermanos Rodríguez in Mexico, and the Calder Park Thunderdome in Australia.

NASCAR has its official headquarters in Daytona Beach, Florida, and also maintains offices in four North Carolina cities—Charlotte, Concord, and Conover. Regional offices are located in New York City and Los Angeles, with international offices in Mexico City and in Toronto. Owing to NASCAR's Southern roots, all but a handful of NASCAR teams are still based in North Carolina, especially near the city of Charlotte.

NASCAR is second to the National Football League among professional sports franchises in terms of television ratings in the United States Internationally, its races are broadcast[by whom?] in over 150 countries. In 2004, NASCAR's Director of Security stated that the company holds 17 of the Top 20 regularly attended single-day sporting events in the world. Fortune 500 companies sponsor NASCAR more than any other motor sport, although this sponsorship has declined since the early-2000s.