Owing to severe illness, Beethoven had to wait for over a year after completing op. 109 before beginning work on the second piece in his triptych of late sonatas: the Piano Sonata in A-flat major op. 110. The initial sketches date from summer 1821: the work was completed by the end of the year and appeared in print the following summer # in an edition so riddled with mistakes that Beethoven angrily complained to the publisher. For this new edition Jonathan Del Mar consulted all known sources and came across previously unknown information in the course of his research. The edition appears with a meticulously edited and elegantly engraved musical text incorporating the latest findings of scholarship, supplemented by a detailed Critical Commentary and notes on performance practice in Beethoven#s day.