A better book of this kind. (But best to study scores.) One quibble: The author calls the lowest note of a secundal chord voiced in seconds its root, and so for quartal chords, and this strikes me as arbitrary and illogical. It doesn't branch from what Rameau ("branch" in English) intended by "root". Readers interested in music theory will probably also want to look at PENTATONIC SCALES FOR THE JAZZ-ROCK KEYBOARDIST by Jeff Burns.

Vincent Persichetti's "Twentieth Century Harmony" is a very thorough look at ways to use harmony outside of a traditional tonal context. In other words, if you are a composer and don't know all you could about how to use harmony except in tonal progressions, or if you are a listener interested in understanding twentieth century concert music, this book is for you. The book deals with the harmonic series, modes, synthetic scales, different types of chords (added note, polychords, etc.) and very specifically with different characteristics of different intervals. Littered with examples of nearly every point, it is the best education on contemporary harmony available.
Persichetti, unlike too many composers, doesn't go out of his way to use as many words as possible. He also doesn't attempt to criticize styles of music not his own in this writing; he simply gives an objective, clear, well organized series of lessons in harmony. I am a senior music composition student now, wondering how I ever got along without this book.

Twentiteh Century Harmony provides, in a concise, easy to follow format, a useful methodology of understanding and manipulating the musical structures of the twentieth century. Written from a teacher's perspective, the book is engaging and full of suggested exercises for the practice of the techniques being discussed in each chapter.