We clarinetists are lucky, we've got 4 major works for clarinet written by Johannes Brahms: the Trio in A minor for clarinet, cello and piano, Op. 114; the Quintet in B minor for clarinet and strings, Op. 115; and Sonatas Nos. 1 and 2, Op. 120. His association with clarinetist Richard Mühlfeld gave the world some great music, and clarinetists some of their best. Too bad he didn't write a concerto for clarinet.
Here's the first movement of the quintet, with that silky lullaby main theme. I was privileged to performed this with my fine colleagues from the Columbus Symphony a number of years ago. I was playing my Lelandais mouthpiece, for those interested.
Written for the A clarinet, Brahms explored the dark lower range of the instrument. He also featured the clarinet's gypsy side in the second movement which I'll post in a few days.