The Piano Concerto No. 15 in B-flat major, KV. 450 is a concertante work for piano and orchestra by Wolfgang Amadeus Mozart. Mozart composed the concerto for performance at a series of concerts at the Vienna venues of the Trattnerhof and the Burgtheater in the first quarter of 1784, where he was himself the soloist in March 1784.
Indeed, many pianists consider this to be one of the more difficult of Mozart’s piano concertos. The concerto is primarily difficult from its many quick scale patterns which must be played perfectly and also from its many fast chord patterns moving up and down.