Sibelius’s published works typically were a result of a goal-oriented process in which the printed score basically was intended as “die Fassung letzter Hand“. However, the composer sometimes made, suggested or planned alterations to his works after publication, and occasionally minor revisions were also included in the later printings. What also complicates the question about Sibelius’s “final intention” vis-à-vis the printed editions is that he obviously was not always a very willing, scrupulous or systematic proofreader of his works. As a result, the first editions, even though generally prepared under his supervision, very often contain copyists’ and engravers’ errors, misinterpretations, inaccuracies and generalisations, as well as changes made according to the standards of the publishing houses. In comparison with the autograph sources, the first editions may also include changes which the composer made during the publication process. The contemporary editions of Sibelius’s works often correspond to the composer’s intentions in the main features, such as pitches and tempo indications, but not always in the details concerning dynamics, articulation and the like. Thus, if several sources for a work have survived, a single source alone can seldom be regarded as reliable or decisive in every respect.

JSW aims to publish Sibelius’s works as thoroughly re-examined musical texts and to decipher ambiguous, questionable and controversial readings in the central sources. Those specifics which have been regarded as copyists’ and engravers’ mistakes, as well as other unauthorised additions, omissions and changes, have been amended. The musical texts are edited to conform to Sibelius’s – sometimes idiosyncratic – notation and intentions, which are best illustrated in his autographs. Although the composer’s notational practice is the basic guideline in the JSW edition, some standardization of, for instance, stem directions and the vertical placement of articulation marks has been carried out in the JSW scores. If any standardisation has been judged as compromising or risking the intentions or interpretational aspects manifested in Sibelius’s autograph sources, the composer’s original notation has been followed as closely as possible.

In the JSW scores the following principles have been applied:

• Instruments and vocal parts are designated by their Italian names.
• Repetitions are indicated with the symbol ./. , and passages annotated with instructions such as col Violino I are written out fully.
• Unpitched percussion instruments are notated on a single line each.
• As a rule, only the original text to which Sibelius composed or arranged a vocal work is printed in the score. Modern Swedish (as well as German) orthography was established during Sibelius’s lifetime, in the early twentieth century. The general orthography of the texts has been modernised, a decision that most profoundly affects the Swedish language (resulting in spellings such as vem, säv or havet instead of hvem, säf, hafvet), but to some degree also texts in Finnish and German.

  Other types of notational features and emendations have been specified case by case in the Critical Commentaries.

Editorial additions and emendations in the scores are shown by square brackets, broken lines (in the case of ties and slurs) or footnotes. Since the use of these indications is connected to and dependent on the source circumstances of each individual work, the principles of their use and other specific editorial questions and procedures have been discussed in each volume.