Teresa headed Dale Earnhardt, Inc. (DEI) during four Busch Series championships in 1998, 1999, 2004 and 2005 plus two Craftsman Truck Series championships in 1996 and 1998. Her first Daytona 500 win as a team owner occurred when driver of the #15 Chevrolet driven by Michael Waltrip won at the 2001 race. The win, however, was overshadowed by her husband's death in a crash during the final lap of the race.