The Piano Trio in B-flat major, Op. 11, was composed by Ludwig van Beethoven in 1797 and published in Vienna the next year. It is one of a series of early chamber works, many involving woodwind instruments because of their popularity and novelty at the time. The trio is scored for piano, clarinet (or violin), and cello (sometimes substituted by bassoon). The key of B-flat major was probably chosen to facilitate fast passages in the B-flat clarinet, which had not yet benefited from the development of the Boehm system. Beethoven dedicated the piece to Countess Maria Wilhelmine von Thun.

Date of composition 1797
First published 1798 in Vienna, Austria
Type Piano Trio
Tonality B-flat Major
Catalogue Op. 11
Instruments Piano
Clarinet
Cello
Autotranslations beta Ludwig van Beethoven: Trio pour piano n°4 en si bémol majeur, Op. 11 "Gassenhauer Trio"
Ludwig van Beethoven: Trio per pianoforte n. 4 in si bemolle maggiore, Op. 11 "Gassenhauer Trio"
Ludwig van Beethoven: Trio Nr. 4 für Klavier B-dur, Op. 11 "Gassenhauer Trio"