Kirkland was a student of Lee Strasberg and a member of the Andy Warhol coterie. She began acting Off-Broadway in 1962, and has been said to have been the first actress to appear nude in legitimate theater, in a 1968 production of Sweet Eros.
After several small roles in such films as The Sting, The Way We Were, A Star Is Born and Private Benjamin, she was nominated for the Academy Award for Best Actress in 1987 for Anna.
Kirkland was unable to follow up the nomination with much success, however, although she did appear on television frequently, including the series Valley of the Dolls and the soap opera Days of Our Lives. She also had a small role in Edtv.
She is a minister in the Church of The Movement of Spiritual Inner Awareness, and teaches drama, yoga and meditation.