Hee Seo is a Korean American ballet dancer who is a principal dancer at the American Ballet Theatre (ABT). Although Seo started Russian ballet training at the age of 12 (an age considered to be a late start for a ballet dancer), she became one of the youngest ballerinas and first Korean ballerina to be promoted to principal dancer in the ABT's 75-year history. In 2015, Seo established the Hee Seo Foundation in Korea to help underprivileged prospective ballet dancers.