Anna Marie "Patty" Duke (December 14, 1946 – March 29, 2016) was an American actress. Over the course of her acting career, she was the recipient of an Academy Award, two Golden Globe Awards, three Primetime Emmy Awards, and a star on the Hollywood Walk of Fame.

At age 15, Duke portrayed Helen Keller in the film The Miracle Worker (1962), a role she had originated on Broadway. She won an Academy Award for Best Supporting Actress for her performance. The following year, she played the dual role of "identical cousins" Cathy and Patty Lane on her own network television series The Patty Duke Show (1963–1966). She progressed to more mature roles, such as Neely O'Hara in the film Valley of the Dolls (1967) and Natalie Miller in the film Me, Natalie (1969). The latter earned her a Golden Globe Award for Best Actress – Motion Picture Comedy or Musical. From 1985 to 1988, she served as president of the Screen Actors Guild.

Duke was diagnosed with bipolar disorder in 1982. Following her diagnosis, she devoted much of her time to advocating for and educating the public on mental health. She was also an occasional singer and author.