Mass No. 5 in A-flat major, D 678, is a mass composed by Franz Schubert, completed in 1822. There is no record of a performance during Schubert's lifetime. It is scored for soprano, alto, tenor and bass soloists, SATB choir with divisi, violin I and II, viola, flute, 2 oboes, 2 clarinets, 2 bassoons, 2 horns, 2 trumpets, 3 trombones colla parte, timpani and basso continuo (cello, double bass and organ). It is classified as a missa solemnis.