Former US Secretary of State Warren Christopher has died of cancer aged 85.
Mr Christopher will be remembered for helping bring peace to Bosnia in the 1990s and negotiating the release of American hostages in Iran in 1981.
His understated manner as top US diplomat from 1993-97 led to his being called the "stealth" secretary of state.
"Careful listening may be the secret weapon," he once said in a speech.
"I observed some time ago that I was better at listening than at talking."
Mr Christopher passed away peacefully at home in California late on Friday after complications from bladder and kidney cancer, his family were reported as saying.
Born on 27 October 1925 in North Dakota, he rose from modest circumstances to become a highly successful Los Angeles lawyer.
Before his career in diplomacy Mr Christopher served as a deputy attorney general under President Lyndon Johnson in the late 1960s.
He made headlines as deputy secretary of state in the Carter administration by negotiating the release in 1981 of 52 American hostages in Iran. His efforts won him the US's highest civilian award, the Presidential Medal of Freedom.
"The best public servant I ever knew," Jimmy Carter wrote in his memoirs.
The following decade saw Mr Christopher deeply involved in efforts to secure peace in the Middle East.
He had more success in the former Yugoslavia, helping end war among Muslims, Serbs and Croats in Bosnia with the 1995 Dayton accords. The conflict claimed more than 100,000 lives, making it the most deadly in Europe since WWII.
Mr Christopher travelled tirelessly for work. He set a new record for the number of air miles clocked up by a secretary of state over a four-year period.
By October 1996, now in his 70s, he had flown 704,487 miles and the crew on his air force plane presented him with a cake to mark the occasion.
The following year he resigned, to be replaced by Madeleine Albright. President Bill Clinton said Mr Christopher had "left the mark of his hand on history".
He also joked that Mr Christopher, who was always immaculately turned out, was "the only man ever to eat M&Ms on Air Force One with a fork".
Warren Christopher is survived by his wife Marie and four children from his two marriages.