The Sonata in A minor for Arpeggione and Piano, D. 821, stands as a unique testament to Franz Schubert's compositional output during a period of personal hardship. Written in November 1824, it is the sole surviving substantial work for the arpeggione, an instrument akin to a bowed guitar. Composed during the same period as the 'Death and the Maiden' Quartet, Schubert was grappling with advanced syphilis and profound depression. Today, the piece is primarily experienced through transcriptions for cello and piano or viola and piano, arranged after its posthumous publication.

The Sonata in A minor for Arpeggione and Piano, D. 821, is recognized as a significant, albeit singular, work in Schubert's oeuvre. Its unique instrumentation and the poignant circumstances of its creation contribute to its historical interest. While the original arpeggione is now rare, the sonata's enduring appeal is evident in its frequent performance and recording in various transcriptions, particularly for cello and piano. This continued engagement highlights the piece's melodic richness and emotional depth, ensuring its place in the classical repertoire.