Sheperd was the first woman to be officially rated #1 World Karate Champion in forms, a title she held for two years, 1979 and 1980. Before 1979, separate ratings existed for female fighters but not for female forms competitors. Often competing against a field of men, Sheperd believed more women would compete if they had a title to compete for. Sheperd organized a petition to establish the title and garnered the support of tournament promoters to begin offering a separate forms division for female competitors. The Editor of Karate Illustrated Magazine, Renardo Barden, established the first official ratings for female forms competitors in 1979. Having gained the highest accumulated 1st place points on the Karate competition circuit, Sheperd achieved the #1 rating by Karate Illustrated Magazine for 1979 and 1980.

Sheperd was the first woman to ever win the Grand Championship title over all male and female forms competitors at the US Open Battle of the Superstars at the Bayfront Center in St. Petersburg, Florida on November 1, 1980. Her victory with her signature chain whip was featured on "The World of People" television show.

As the nation's top-rated woman, Karen Sheperd continued her dominance by defeating Belinda Davis, Cynthia Rothrock and Lori Clapper in Women's Black Belt Forms at the Diamond Nationals on May 2, 1981 in Minneapolis, Minnesota.

In 1992 Sheperd was voted the "Most Popular Female Martial Arts Superstar" by readers of Inside Kung Fu Magazine. In 1997 Sheperd was inducted into the prestigious Black Belt Hall of Fame as "Woman of the Year". In 2002, she was inducted into the Martial Arts History Museum Hall of Fame.