Steber was one of the most important sopranos in the United States during the 1940s and 1950s, with a sweet, yet full voice and outstanding versatility. Her recitals were practically vocal pentathlons for their wide range of styles and vocal demands, and the day she sang Desdemona in Verdi's Otello for a Met matinee and Fiordiligi in Mozart's Così fan tutte that evening is still legendary. She is perhaps most famous for her creation of the title role in Samuel Barber's Vanessa (actually as a substitute for Sena Jurinac), and for commissioning his Knoxville: Summer of 1915. In addition to opera and recitals, she was a frequent guest on #The Voice of Firestone's television broadcasts. However, her career outlasted her voice, and most of her later appearances and recordings were gravely technically flawed.

Her mother was an accomplished amateur singer who strongly encouraged her to study and sing in school and community shows. She entered the New England Conservatory of Music, originally intending to major in piano, but her voice teacher, William Whitney, persuaded her to focus on singing instead. Her opera debut was in 1936 in a WPA production of Wagner's The Flying Dutchman, a demanding role indeed for a 21-year-old. She won the 1940 Metropolitan Auditions of the Air and made her Met debut later that year as Sophie in Strauss' Der Rosenkavalier. Her easy upper range, coupled with a rich, smoothly produced lower voice made her a natural for Mozart roles such as the Countess in Le nozze di Figaro, Pamina in The Magic Flute, and even Konstanze in the Abduction from the Seraglio, with its vocal pyrotechnics. As her voice matured, she sang some of the spinto roles in both the German and Italian repertoire, including Tosca, Desdemona, Elsa in Lohengrin, and the Marschallin in Der Rosenkavalier. She also sang Marie in the first Metropolitan production of Alban Berg's Wozzeck in 1959. Her relationship with the Met was not an easy one, for many reasons on both sides, and she turned her attention more and more toward recitals and concerts during the 1960s. She and her husband opened and managed a record label, ST/AND (combining their names), but when they attempted to expand, it was a dismal flop. She made some appearances on Broadway, mostly in supporting parts, and also gave one of the notorious bathhouse concerts in New York in 1973., Rovi