The Serenade, Op. 41 is based on Beethoven's Op. 25 for flute, violin and viola. The version for piano and flute (or violin) did not originate from the composer – but was probably undertaken by the composer Franz Xaver Kleinheinz. Beethoven did, however, "look through it and substantially improve some passages", as he assured his publishers Hoffmeister & Kühnel in September, 1803.