The Symphony No. 33 in B flat major, K. 319, was written by Wolfgang Amadeus Mozart, and dated on 9 July 1779. It was later revised, probably in 1782 or 1785 The symphony has 4 movements, and is scored for strings, 2 oboes, 2 bassoons, and 2 horns, the smallest orchestral force employed in his last ten symphonies.