Walter Klien has been played on NTS shows including Slime w/ Little, with Piano Concerto No. 23 In A Major, K. 488 first played on 4 March 2019.

Walter Klien (November 27, 1928 - February 10, 1991) was an Austrian pianist.

Klien was born in Graz. His mother was the artist Erika Giovanna Klien (1900-1957). She emigrated to the United States in 1929, and their only further contact was by correspondence.

Klien studied piano with Josef Dichler at the Music Academy in Vienna and with Arturo Benedetti Michelangeli. He also studied composition with Paul Hindemith.

He was a laureate of the Busoni Competition in Bolzano and the Marguerite Long Competition in Paris and made his debut in the United States in 1969. He was awarded the Bosendorfer Prize in Vienna in 1953.

Shortly before his death in 1991 he was honoured with the Joseph Marx Music Prize in 1987 and the honorary gold medal of the city of Vienna in 1989.

His discography includes the complete solo piano works and many of the piano concertos of Mozart, the piano music of Brahms, as well as the complete piano sonatas of Schubert. He partnered Arthur Grumiaux in recording the Mozart music for piano and violin.

He performed and recorded piano duo and duet repertoire with his wife, Beatriz Klien.

He was much admired for his crystalline tone and projection of detail in his interpretations. His clarity of playing suited the music of Mozart and Schubert in particular. These qualities are also very evident in his Brahms recordings, where the dense textures of the writing can easily obscure the musical argument. A small number of critics continue to regard his complete Schubert sonatas as amongst the very finest yet recorded, not least for their unique Viennese lilt and unaffected ease.

David Dubal, in the second edition of "Reflections from the Keyboard", says One of his finest achievements are his recordings of the complete piano music of Brahms, which he played with intelligence and a high degree of emotion.