Harriet Fleischl Pilpel (December 2, 1911 – April 23, 1991) was an American attorney and women's rights activist.

Pilpel served as general counsel for both the American Civil Liberties Union and Planned Parenthood.

[1] During her career, Pilpel played a role in 27 cases that were heard by the Supreme Court of the United States.

Law writes that Pilpel "was a brilliant legal tactician with a deep knowledge of the nuance of doctrine, but she was also acutely attuned to political opinion, organizational politics, the press, religious feeling, and the broad cultural forces that shape constitutional principles.

Through her work with Greenbaum, Wolf & Ernst, Pilpel was involved with the birth control movement, taking cases such as State v. Nelson (1940) and Tileston v. Ullman (1943).

She supported the struggles to overturn birth control laws at the state level, working alongside movement activist Margaret Sanger.

Her clients included Betty Friedan, Mel Brooks, Billy Graham, Edna Ferber, Svetlana Alliluyeva, Jerome Kern, and Erich Maria Remarque.

In 1961, she argued on behalf of Planned Parenthood in Poe v. Ullman, asking the Supreme Court to reverse a Connecticut law criminalizing birth control.

[9] Alongside Aryeh Neier, Pilpel helped organize the campaign against New York's anti-abortion law.

[9] She authored Planned Parenthood's amicus brief for Roe v. Wade and strategized with attorneys Sarah Weddington and Linda Coffee, organizing moot court practices prior to arguments in the case.

[10] She argued in 1977's Carey v. Population Services International on behalf of a minor's right to acquire contraceptives without parental consent.