Having learned to know the clarinet in 1778 in Mannheim, Mozart loved the warm and expressive sound of the instrument. It is to his friendship for Anton Stadler, the clarinetist of the orchestra of the Imperial Court of Vienna, that today, in addition to the Concerto for clarinet and orchestra K. 622, this quintet of quintets, composed by Mozart two years before his death. Like most of Mozart's clarinet works, the K. 581 Clarinet Quintet was probably originally written for the basset horn (alto clarinet). Only two posthumous editions have been preserved, both of which contain the clarinet in La- it is on these sources that our edition is based. In addition, the instrumentalists requested will find in appendix the fragment of an Allegro in B flat major?