Horsford currently has a recurring role as Vivienne Avant on The Bold and the Beautiful. For the role, she was nominated for Outstanding Special Guest Performer in a Drama Series in the 43rd Daytime Emmy Awards.
Horsford was born in Harlem in 1948 to Victor Horsford, an investment real estate broker originally from the Dominican Republic, and Lillian Agatha (née Richardson) Horsford, emigrated from Antigua and Barbuda in the 1940s. According to a DNA analysis, she has maternal ancestry from the Limba people of Sierra Leone.
Her first major role in television was as a Producer for the PBS show Soul!, hosted by Ellis Haizlip, which aired between 1967 and 1973. Horsford made guest appearances on such sitcoms as The Fresh Prince of Bel-Air, Sparks, Moesha, The Bernie Mac Show, The Shield, Girlfriends, and Everybody Hates Chris. She had main roles on the sitcoms The Wayans Bros. as "Dee Baxter" and "Thelma Frye" on Amen. She appeared on the drama Judging Amy.
Horsford is best known for her roles as Thelma Frye on the NBC sitcom Amen (1986–91), and as Dee Baxter on the WB sitcom The Wayans Bros. (1995–99). She had dramatic roles on the FX crime drama The Shield playing A.D.A. Beth Encardi, and CBS daytime soap opera The Bold and the Beautiful as Vivienne Avant, for which she was nominated for a Daytime Emmy Award for Outstanding Special Guest Performer in a Drama Series in 2016.
Horsford appeared in a number of movies, most notable as Craig Jones' mother Betty in 1995 comedy film Friday and its sequel Friday After Next (2002). Her other film credits include Times Square (1980), The Fan (1981), Presumed Innocent (1990), Set It Off (1996), Along Came a Spider (2001), Our Family Wedding (2010), and A Madea Christmas (2013).
On October 29, 2011, Horsford was awarded the title of Ambassador of Tourism of Antigua.
More recently, she was seen in the first season of Grey's Anatomy. She returned to the big screen in the 2013 film A Madea Christmas. She portrayed Helen on the BET sitcom Reed Between the Lines.
