Op. 120, No. 1, also entitled Opus 120, No. 1 or in its German form, Opus 120, Nr. 1, is a 1986 arrangement for clarinet and orchestra of Johannes Brahms's Clarinet Sonata Op. 120, No. 1 by Italian composer Luciano Berio. As with the original Sonata, the soloist in this arrangement can either be a clarinet or a viola.