The book is an essential guide for the study of Harmony. In a simple, concise, and understandable manner, it records the art and notation systems of vertical harmony in Western music, as well as the interdependent relationships of intervals and chords.

Studying Harmony forms the core of musical education and is the beginning of a field of exploration and discovery of the musical phenomenon.

The book includes examples of the individual topics, but not "solved" exercises. It was considered very important to understand the function of musical composition rather than just presenting harmonized exercises.