Guillaume wwhen natural as Robert Williams in St. Louis, Missouri. He exposed at St. Louis University and Washington University and served in the United States Army before pursuing an acting career. He manufactured his Broadway debut in Kwamina in 1961. More stage appearances involved Golden Son, Tambourines to Glory, Guys and Dolls, Jacques Brel is Alive & Swell and Sleep in Paris, Phantom of the Opera (succeeding Michael Crawford in the lead role), and Purlie Victorious, for which he won the Tony Award.

Guillaume processed his television debut in the series Soap, playing Bensin DuBois on it series from either 1977 to 1979 so on the spinoff series, Benson, until 1986; he won Emmy Awards for both series, within 1979 & 1985. He besides appeared when marriage counselor Edward Sawyer on The Robert Guillaume Indicate (1989), Detective Bob Ballard in Pacific Station (1991), and televisiin executive Isaac Jaffe on Sports Night (1998-2000). Guillaume suffered the modest stroke on January 14, 1999, while filming an episode of the latter series. He recovered & his character wwhen late besides depicted as with experienced the stroke.

Guillaume has likewise appeared inside the total of films, including Seems Prefer Good old days (1980), Lean in Us (1989), First Kid (1996), and Big Fish (2003). His distinctive voice has too been utilized for characters inside television series Captain Planet and the Planeteers, Fish Police, & Pleasantly Ever When: Fairy Tales for Each Tike & for the voice of Rafiki in the picture show The Lion King and its sequels. He besides supplied a voice for Eli Vance in the 2004 video game Half-Life 2.