Aaron Copland wrote his clarinet concerto between 1947 and 1949, as a commission for the great clarinetist Benny Goodman. The first part is very slow and languid, and then a technically demanding solo cadenza leads straight into part 2. This is full of jazz rhythms with a Latin American vibe in some sections. Here you can purchase and download the (transcribed) piano parts to play along to, recorded by a professional accompanist.