The genesis of one of Mozart's best-loved piano works, his Fantasy in d minor, is still shrouded in darkness. Even Mozart's sister, who came across the work in 1807 through the first edition, was astounded to have discovered a previously unknown composition of such quality. In its original form the Fantasy was in all probability a fragment. The closing bars that are most frequently performed today originated from an unauthorized print from 1806. We have also included these in our edition due to the lack of any others in Mozart's own hand or any other authorized source. Our single edition was put together using the musical text from the revised complete volume ''Mozart Piano Pieces'' (HN 22 and 9022).?