Ms. Duke, whose career began in the 1940s, was a founding member of Americans for UNFPA. A stalwart champion of family planning, she focuses on population and development projects that incorporate human rights with health care for women. Duke co-founded the United States-Japan Foundation, worked extensively in Asia and Africa for women’s health, and was appointed Ambassador to Norway during the Clinton Administration. She was born Grace Esther Tippett in Baltimore on Oct. 13, 1923, one of two daughters of Richard Edgar and Esther Chandler Tippett. Her parents called her Robin, and she used the nickname all her life. Her father left his law firm when she was 15, and the family fortunes went into a tailspin. Robin had to drop out of a private school for girls. Her parents split up. She used the byline Robin Chandler and covered society news, fashion and the occasional murder. In 1946, she quit the newspaper, married the actor Jeffrey Lynn and moved to Hollywood. His film career had flourished in the late 1930s and early ’40s (he played alongside James Cagney and Humphrey Bogart in Raoul Walsh’s “The Roaring Twenties”), but it faltered after he served in World War II. The Lynns had two children, Jeffrey and Letitia. As Mr. Lynn’s film career dwindled, it largely fell to Robin to support the family. With her background in journalism, she got a job at WCAU-TV, the CBS affiliate in Philadelphia, reading the evening news. The Lynn marriage came apart in the early 1950s, although the couple did not divorce until 1958. In 1952, she joined NBC’s new “Today” show, with Dave Garroway, as an anchor-reporter. She covered the national political conventions and Jacqueline Bouvier’s 1953 marriage to Senator John F. Kennedy. From 1953 to 1958, she was a broker at Orvis Brothers, and then, for four years, she was vice president for public relations at Pepsi-Cola. At age 39, she became the fourth wife of Angier Biddle Duke, the scion of two American dynasties. He was President John F. Kennedy’s chief of protocol, had already served as ambassador to El Salvador and would later become President Lyndon B. Johnson’s chief of protocol and the ambassador to Denmark, Spain and Morocco. His father, Angier Buchanan Duke, was heir to part of the American Tobacco Company fortune, most of which went to his cousin, Doris Duke. Mr. Duke’s mother was Cordelia Drexel Biddle, a Philadelphia socialite and writer. The Dukes had one son, Angier Jr. Ms. Duke’s husband retired from diplomatic service in 1981. He died in Southampton in 1995 after being hit by a car while rollerblading. Besides her daughter Letitia, Ms. Duke is survived by two other children, Jeffrey Lynn and Angier Biddle Duke Jr. (known as Biddle); two stepchildren, Marilu Duke Cluett and Dario Duke; and four grandchildren.