Following the standards and purpose of the series, this volume comprises an extensive introduction and the edition of the office itself. The introduction, written in German, consists of two parts: Mechthild Pörnbacher discusses the text of the office and its author, and David Hiley introduces the music. Pörnbacher starts by relating the life of St Fridolin (d. c.530), an Irish missionary who in a vision he had on the grave of St Hilary of Poitiers saw the place where he should establish a monastery. He travelled up the Rhine, and recognising in Säckingen (now Bad Säckingen in Baden-Württemberg, on the border with Switzerland) the place from the vision, established a convent there. (Does the map on p. xx show his surmised journey?) The author continues with the life of Balther von Säckingen: although born as a serf of the convent at Säckingen, he studied in Sankt Gallen, with Notker II as one of his teachers; after years of intermittent travel he was ultimately appointed as Bishop of Speyer, where he died in 986 or 987. Balther composed the lives and the offices of both St Hilary of Poitiers and St Fridolin. As can be surmised from a surviving letter, he dedicated his work to his teacher Notker II. Pörnbacher quotes Balther's account of the feast of St Fridolin (and briefly mentions modern celebrations too, though these cannot be compared in significance); she puts Balther's literary work into the wider historical context of tenth-century Gaul, comments upon the text of the office, and finally describes two main sources of Balther's output. More detailed information about all these topics is available in Pörnbacher's monograph on Balther, which is referred to throughout.

At this point, the discussion passes over to music. David Hiley explains that Balther's office was hitherto known only from one notated source, a twelfth-century manuscript from Säckingen (now in Karlsruhe, hence ‘K’ in the edition), which contains Balther's complete output with music in German adiastematic neumes. Some time ago, he found a more recent copy of the office – in a late-sixteenth-century antiphoner (now in Einsideln, hence ‘E’), written in Gothic notation on the stave. The discovery enabled a modern edition of the work. Hiley compares the notation of K with that of E, establishing that some of the signs in the earlier manuscript do not have equivalents in the more recent one (liquescents, oriscus, quilisma), meaning that melodies of E do not exactly match those of K. A detailed comparison of the melodies of both sources shows a number of variant readings; furthermore, for a couple of items, E clearly presents quite different melodies. These differences render the reconstruction of the melodies of K impossible. In the continuation, Hiley concentrates on the dedication mentioned above, in which Balther asks his teacher ‘utrum iste presens libellus una cum cantilena responsoriorum, que per musicam artem in festivitate sancti Fridolini canenda composui, flammarum incendio sit delendus, an ad Dei servitium posthac reservandus’. He proposes several explanations of Balther's interesting declaration that he composed the responsories ‘according to the art of music’. Balther obviously did not compose arbitrarily, and one is tempted to assume that he followed the paradigms he had encountered in Sankt Gallen, which makes his music especially interesting historically. In the dedication, Balther mentions only responsories (but no antiphons); as the Matins antiphons of the office follow the progressive modal order, which is not the case with the responsories, Hiley speculates that Balther might in fact have written only responsories, and that the antiphons were a later addition to complete the office. The introduction to music is rounded off by the discussion on the musical aspects of the office, in which Hiley presents the modal order (limited only to the Matins antiphons), mentions typical Gregorian phrases, and enumerates the responsories with standard verses.

The edition of Balther's work follows the policy of the series by including all elements of the office (rather than just musical ones), because of which it makes use of some other appropriate sources. For every item of the edition, the relevant source is quoted. The texts of Balther's office are transcribed from E, as are the melodies, which are, in addition, supplied with facsimiles of the appropriate chants from K. The decision to include the facsimiles of the older adiastematic versions of the chants seems reasonable: on the one hand, it enables an insight into the musical history of the office, and on the other, it allows hypothetical reconstructions of some of the chants in K. The texts, equipped with diacritical signs and capital initials according to modern standards, retain the original spelling; as they come from different sources, the orthography of single words varies slightly (e.g., in the spelling of diphthongs). There is some ambiguity regarding the identity of the lessons. Those of the first and second Nocturn are taken from a printed breviary of Constance from c.1475; the first four come from Balther's Vita of the saint (according to information at the end of the lessons), whereas the fifth and the sixth, which also relate the events from the saint's life, come from a certain ‘Legenda aurea’ (though Jacobus de Voragine does not appear to have written the legend of St Fridolin). The homily of the third Nocturn is again from K; however, Pörnbacher's description of the manuscript (some pages back) makes no mention of homilies. Is the homily in question also Balther's work? The knowledge concerning these tiny details is no doubt available in Pörnbacher's monograph.

The melodies are transcribed according to the accepted standard principles: groups of notes (black heads) stand for the signs of Gothic notation, slurs indicate the original ligatures; strophici and liquescents (very rare) are designated. Phrasing signs, which are to some extent interpretative, observe the musical substance of the melodies. Conceived in this way, the musical edition serves both as a reliable scholarly transcription of the original sources and as a performing edition including unassertive and unobtrusive hints at the musical interpretation of Balther's music.

The new edition addresses a number of issues and enables their scholarly investigation. Among the interesting topics that especially call for further consideration are: the relationship between the two versions of the office; the correspondence between the antiphons and the psalms, and the correspondence between the lessons and the responsories; as well as the stylistic characteristics of the music and its musical integrity. Besides this, Balther's music can now be compared with other contemporary offices, and his melodies can be incorporated into the databases enabling the already advanced computer analyses of music of medieval historiae in their historical perspective. This edition of Balther's music is without doubt an important contribution to our understanding of medieval liturgical monody.