American soprano noted for the beauty and richness of her voice and for the thought and sensitivity she brought to the texts. Fleming's repertoire was extraordinarily broad, spanning three centuries and ranging from Handel and Mozart through 19th-century bel canto to the works of a number of contemporary composers.

Fleming grew up in Rochester, New York, where her parents taught music in high school. She began music lessons as a young child and as a college student had success as a jazz vocalist. In 1981 she graduated from the State University of New York at Potsdam with a degree in music education. She continued her studies at the Eastman School of Music at the University of Rochester and the Juilliard School's American Opera Center in New York City. She spent 1984–85 on a Fulbright fellowship in West Germany, where she studied with Arleen Augér and Elisabeth Schwarzkopf (Schwarzkopf, Dame Elisabeth). Fleming made her professional debut in Salzburg, Austria, in 1986. Two years later she won the Metropolitan Opera National Council Auditions, followed by the George London Award and the Richard Tucker Award.

Among Fleming's more admired roles were Fiordiligi in Mozart's Così fan tutte, Marguerite in Charles Gounod's Faust, the Marschallin in Richard Strauss's Der Rosenkavalier, Ellen Orford in Benjamin Britten's Peter Grimes, and the title characters in Handel's Alcina, Jules Massenet's Manon, Antonín Dvořák's Rusalka, and Carlisle Floyd's Susannah. She sang the world premieres of the countess in John Corigliano's The Ghosts of Versailles (1991), of Madame de Tourvel in Conrad Susa's The Dangerous Liaisons (1994), and of Blanche DuBois in André Previn's A Streetcar Named Desire (1998). Fleming recorded extensively and won numerous honours, including the Outstanding Contribution to Music Award at the 2004 Classical BRIT Awards. She published The Inner Voice: The Making of a Singer in 2004.