Conceptualizing the sound of medieval music has always been a problem for modern scholars and performers. This is due to three elements: medieval music incorporates a vocal style that is different from that currently employed in the presentation of art music; the early medieval notational system, as we know it, is still only partially understood; and medieval music had an elaborate and involved tradition of extemporized ornamentation. McGee begins his introduction by stating that his research has concluded that the entire early vocal style of medieval music itself is ornamental (his emphasis), and that the reader should think of the two elements of vocal ornamentation and vocal technique in medieval song as essentially the same. McGee then goes on to explain that, in his reading of over 150 treatises, of which excerpts from forty-six are included in an appendix, vocal ornamentation and embellishment of medieval song was actually the rule rather than the exception.

Although this book is not intended to be a manual of practical application (the author indicates that he intends to publish a separate volume directed at the practical level), McGee still provides numerous musical examples and directions for current performers and ensembles of medieval song. According to McGee, the concepts of ornamentation and elaboration were basic both to medieval composition and performance. His theoretical sources encompass the dates c.600 to c.1490, and deal with both monophony and the invention and development of polyphony. Each chapter presents information gleaned from the treatises, translated for the reader, but also included in their original language in the appendix.

The chapter titled "Vocal Style and Technique" provides an overview of the desirable performance traits necessary for singing both monophony and polyphony in the Middle Ages according to the treatises. Basically, a singer had to have a bright and well-supported voice that projected from the front of the mouth and articulated with agility and grace, and the technique to express the text and shade sounds. Specific performance instructions for articulation, tempo, and expression are also provided by the author, again using the treatises as his justification.

"Written Ornamentation" is a study of the 'ornamental' neumes found in early and later medieval notational systems. A detailed documentation of liquescent neumes ( plica, gutturalis, sinuosa, clivis, pes, quilisma, and oriscus) and repercussive neumes (stropha and pressus) according to the treatises follows. The author summarizes that medieval vocal technique had within its basic vocabulary such sounds as throat vibrato, indefinite pitch, sliding and pulsing sounds, and inflected tone, as well as the more normal full tone and stable pitch.

The chapter on "Graces" discusses improvised ornaments, according to the treatises. This includes information about the nature of the ornaments, their placement in the writings, and the technique of performance. The author discusses terms such as vibrato/trill, reverbation/appoggiatura, accented appoggiatura, comminutio, tremula, and morula. Interval and pitch variation in medieval song is also examined, with extensive reference to the surviving treatises.

The "Passaggi" chapter deals with ornaments that were meant to connect written notes, or in some cases replace what was written. The author presents information on the performance of organum purum, and also presents examples of how extended passaggi such as cadenzas, introductions, and caudae were performed in medieval song. Instructions on the fermata and signum congruentiae are also discussed, as well as special instrumental instructions provided in the treatises.

The author presents all of his findings in the "Conclusion", providing an extended dissertation on probable development of medieval vocal production and dissemination from the ninth century through the fourteenth and fifteenth centuries. McGee also describes the medieval singing style in concrete and definable terms, according to the surviving evidence of the treatises. He mentions that the type of singing style used in the Middle Ages is probably very similar to the current styles used in the Eastern Mediterranean countries and in India; that is, it is closely related to Eastern singing traditions. McGee summarizes his research on all of the 'ornaments' used in medieval song here, and provides an excellent reference for performers and ensembles of medieval song in this chapter.

McGee's contribution to the continuing research related to the sound, performance, and understanding of medieval song is both relevant and thorough. The numerous charts, tables, and musical examples illustrate and support the author's conclusions. The book presents a strong, basic understanding of the style of singing and ornamentation in the Middle Ages, how it changed over the centuries, and a more general impression of the stylistic differences from one geographic area to another.