[2] Geyer made her professional opera debut in 1979 while a graduate student at Indiana University; singing the role of Xenia in a concert version of Boris Godunov with the St. Louis Symphony Orchestra.
She had previously made her professional concert debut with that orchestra in 1977 performing as the soprano soloist in Ludwig van Beethoven's Choral Fantasy.
Gwynne Geyer has a big, gleaming soprano with effortless high notes, and she shaped her long laments with musical elegance."
In recent seasons Miss Geyer has been heard in a variety of roles on the great stages of the world, among them, Musetta in La Bohème for the Metropolitan Opera, Jenufa at La Fenice in Venice, Rusalka with the Seattle Opera, the title role of Katya Kabanova and Musetta at the Paris Opéra Bastille, Madame Lidoine at the Netherlands Opera in Amsterdam, Freia in Das Rheingold in Madrid, Elsa in Lohengrin at the Liceu in Barcelona, and the title role of Jenufa at the Teatro San Carlo in Naples which was reported in London's monthly Opera (British magazine): "Gwynne Geyer as Jenufa herself added yet another superb characterization to her gallery ... and singing with that distinctive vocal timbre of hers that conveys (especially at the top) a kind of ecstatically painful sincerity."
She sang the title role in Richard Jones' production of Jenufa at the Netherlands Opera, the title role in the Santa Fe Opera premiere of Countess Mariza, Mila Valkova in Janáček's Osud with the VARA Radio in Amsterdam, and a critically acclaimed portrayal of Galina Vishnevskaja in Marcel Landowski's Galina with Opéra National de Lyon.