This is a book for very advanced/professional players wanting to explore modern micro-tonal music. There is nothing about music from other parts of the world that do not use Western European temperaments - for example, the differences between "quarter tones" in Turkish, Persian and Arabic music. It seems to assume equal temperament, without explicitly stating this, and there is no concrete definition of what exactly a quarter tone is. (At this level it would be reasonable to assume that the reader understands cents.) Also, there is nothing on the musical qualities and usage of these notes and intervals. In my opinion, all that is left is a series of empty technical exercises with no cultural or artistic context.