Harriet Fleischl Pilpel was born in New York City in 1911 to businessperson Julius and Ethel (Loewy) Fleischl. She was graduated from Vassar in 1932 and received a Master's degree in 1933 and a law degree in 1936, both from Columbia University.

She married Robert Pilpel, a social service executive on June 15, 1933. They had two children, Judith Ethel Pilpel Appelaum and Robert Harry Pilpel.

Harriet Pilpel was a member of the New York Bar and senior partner in the law firm of Greenbaum, Wolff & Ernst who specialized in First Amendment issues. Between 1937 and 1991, she participated in twenty-seven cases before the U.S. Supreme Court. A prolific lecturer and author of publications related to copyright, abortion, marriage, birth control, civil liberties, and the law, she was also active in many organizations including the board of directors of Planned Parenthood Federation of America for whom she was legal counsel. Pilpel was also counsel to a number of other associations, including Sex Information and Educational Council of the United States, Association for the Study of Abortion, and Association for Voluntary Sterilization. In addition, she served on the boards of the National Abortion Rights Action League, the American Civil Liberties Union, and The Alan Guttmacher Institute. She died in her sleep April 23, 1991.

The Harriet F. Pilpel Papers consist of 13.75 linear feet and are primarily related to her professional work with sexual and reproductive rights, dating from 1913 to 1981. The bulk of the papers date from 1966-81 and focus on sexual rights and liberties. The collection is essentially Pilpel's reference files, and is primarily composed of court documents from various legal cases on the state and federal level, as well as newspaper clippings and articles. There is very little personal correspondence or other materials that are not accessible through the public domain in the collection. However, the files allow for a comprehensive, state-to-state comparison of a variety of sexual and reproductive laws, and provide a sense of the debates going on in individual states and the country regarding sexual and reproductive issues. Types of material include correspondence, memoranda, press releases, reports, legislation, notes, journal and newspaper articles, and court documents.

Major topics found throughout these papers include family planning, abortion, contraception, sterilization, as well as the funding of these activities. Related topics include consent and notification for family planning activities, distribution and advertisements related to sex, sexual activities, and the sexual and reproductive rights of minors. The subject "reproductive rights" serves as an all-inclusive category that contains information about subjects such as maternity rights and population, as well as materials related to several aspects of sexual rights and liberties. "Minors" includes all subjects related to minors except the sterilization of mentally incompetent minors, which is located with the materials related to the sterilization of the mentally incompetent. Organizations represented include the American Civil Liberties Union (ACLU); National Abortion Rights Action League (NARAL); Planned Parenthood Federation of America (PPFA), briefly known as Planned Parenthood-World Population; the Association for the Study of Abortion; and the Association for Voluntary Sterilization. Prominent Supreme Court cases documented include Griswold v. Connecticut (1965), United States v. Vuitch (1971), Eisenstadt v. Baird (1972), Roe v. Wade (1973) and Doe v. Bolton (1973), Bellotti v. Baird (1975), T.H. v. Jones (1975), Planned Parenthood of Central Missouri v. Danforth (1976), and Carey v. Populations Services International (1977).

This collection is organized into two series:

• I. United States
• II. Individual States and Territories
• III. International
• Oversize Materials