Walter, together with Otto Klemperer worked with Mahler, and his performances of Mahler's works are considered outstanding, particularly his recording of the Ninth Symphony, for which he gave the first performance.
He also gave the first performance of Mahler's Das Lied von der Erde, which he later recorded in a famous recording with Kathleen Ferrier. Other first performances by Walter include Pfitzner's Der arme Heinrich.
He performed the works of another Viennese composer, Anton Bruckner, and his recording of that composer's ninth symphony is also a landmark performance.
Walter was a distinguished conductor of music from the classical period, and his recorded performances of Haydn, Mozart and Beethoven are well loved. He also directed opera, and gave productions of Mozart operas at the Metropolitan Opera which are now available on CD, together with his performances of Beethoven's Fidelio.
Walter's discography includes: