DeVore began modeling in 1938 at the age of 16, working primarily for Ebony magazine. In 1946, she and four friends co-founded Grace del Marco Models; in addition to Diahann Carroll and Cicely Tyson, the agency represented such notable figures as Richard Roundtree (“Shaft”), Gail Fisher (“Mannix”); Trudy Haynes, one of the first African-American female TV reporters; and Helen Williams, one of the first successful African-American models. The agency sought to encourage the media to portray African Americans in non-stereotypical ways.
DeVore took on mainstream publications, advertisers and other agencies who avoided hiring African-American models, and she was a tough businesswoman proud of her accomplishments. She once sued Life Magazine after it published a story in 1969 on Black models for which she was interviewed; the resulting article cited white-owned agencies instead.