Flora Rheta Schreiber (April 24, 1918 – November 3, 1988), an Americanjournalist, was the author of the 1973 bestsellerSybil, the story of a woman (identified years later as Shirley Ardell Mason) who had a dissociative identity disorder and allegedly had 16 different personalities. As Mason had insisted on protection of her privacy, Schreiber gave her the cover identity of Sybil Isabel Dorsett.