This publication of a new completion of the Mozart Requiem offers a source-critical edition of Mozart's fragmentary Requiem as well as an alternative to the traditional Süssmayr version. It makes it possible to perform the fragment, identified in print in both the score and the parts; the authentic sections left incomplete by Mozart, now in a stylistically appropriate orchestration; and those sections missing entirely in the fragment, newly added in Mozart's idiom taking into account historical additions by Süssmayr and Eybler.