She was born Patricia Beth Reid in Tularosa, New Mexico. She was a drama major at the University of New Mexico and later studied at the Pasadena Playhouse.

Stanley was a successful Broadway actress with only a few motion picture roles. She was singled out by the New York Times critic Brooks Atkinson for her early work. She eventually attended The Actor's Studio, studying under Elia Kazan and Lee Strasberg.

She starred in such Broadway hits as Picnic (play) (1953), playing Millie Owens, and Bus Stop (play) (1955), playing Cherie.

She received the 1952 Theatre World Award for her performance of Anna Reeves in The Chase; and was nominated for the 1959 Tony Award for Best Actress in a Play for A Touch of the Poet and the 1962 Tony Award for Best Actress in a Play for A Far Country.

Stanley was also the leading lady of live television drama, which flourished in New York City during the 1950s. Among her many starring roles was Wilma, a star-struck 15-year-old girl from the U.S. Gulf Coast of Texas in Horton Foote's A Young Lady of Property, which aired on the Philco-Goodyear Television Playhouse April 5, 1953.

A savaging by English critics after her London performance of Masha in The Actor's Studio production of Anton Chekhov's play The Three Sisters (play) (1965) made her vow never to perform on stage again, a vow she kept for the rest of her life.

Stanley had four husbands, Bruce Hall (married 1945-divorced 1946), Curt Conway (married 1949-divorced 1956), Alfred Ryder (married 1958-divorced 1964) and Joseph Siegel (married 1964-divorced 1967).

She had three children, one by Conway, one by Brooks Clift (brother of Montgomery Clift) while she was married to Conway, and one by Ryder.

Her first movie was The Goddess (1958), playing an unstable movie star, Rita Shawn. In 1964, she starred in Seance on a Wet Afternoon and was nominated for the Best Actress in a Leading Role.

Other movies include Frances (1982), playing the mother of movie star Frances Farmer opposite Jessica Lange, in which she was nominated for the Academy Award for Best Actress in a Supporting Role and a Golden Globe for Best Actress in a Supporting Role - Motion Picture. She also played Pancho Barnes in The Right Stuff (1983).

She received an Emmy Award for Outstanding Single Performance by an Actress in a Leading Role in the episode A Cardinal Act of Mercy on the TV series Ben Casey (1963) and an Emmy for Outstanding Supporting Actress in a Limited Series or a Special for playing Big Mama in Tennessee Williams' Southern melodrama Cat on a Hot Tin Roof (1985).

Kim Stanley died of uterine cancer at her home in Santa Fe, New Mexico at the age of 76. She was survived by her first husband, Bruce Hall, her brother Justin Truman Reid, and her three children. Her biography, Female Brando: the Legend of Kim Stanley by Jon Krampner, will be published in the spring of 2006 by Back Stage Books, a division of Watson-Guptill Publications.