A digital music edition that follows the principles implemented in the fully-digital, MEI-coded Digital Interactive Mozart Edition, pursued by the Mozarteum Foundation and the Packard Humanities Institute, has many advantages over conventional analog editions. One advantage is greater transparency, which is achieved not only at the level of the material, e. g. the inclusion of digital images of the sources, but above all by making editorial processes and decisions visible in the edition itself. In the digital edition, the Critical Report, a defining component of any critical edition and often physically separate from the edited musical text, becomes part of the overall digital code. The philological findings and editorial processes reported encompass the entire range of forms of expression, from verbal comments and annotations to pure code and non-verbal, largely visual communication strategies. Therefore, the format of the traditional printed Critical Report, which is mainly made up of text and tables, dissolves and is replaced by an immaterial, non-delimitable field of data, information, references and media for which the term Critical Documentation is more appropriate.