In the late 1980s and early 1990s, Seymour appeared in numerous issues of the Sports Illustrated Swimsuit Issue and on the cover of Vogue as well. During the same period, Seymour was a primary lingerie and hosiery model for the relatively new Victoria's Secret company in its mail-order catalogs and retail stores. In March 1991, and again in February 1993, Seymour posed for Playboy. She was one of the most famous supermodels of the 1980s and 90s along with Kate Moss, Naomi Campbell, Linda Evangelista, Christy Turlington, Cindy Crawford, and Claudia Schiffer. The magazine Vanity Fair would later have Naomi, Linda, Christy, Cindy, Claudia, and Stephanie cover an issue photographed by Mario Testino, called "—A League Of Their Own. "