On Composition is a series of chapters on the processes and approaches used by composers of classical music.
It is as non-technical as possible, and uses a variety of musical examples from Mozart to Crumb.
Chapters 1-3 are introductory, and address what music is and how listeners and composers approach the perception and creation of it.
Chapters 4-8 are the heart of the matter, introducing useful concepts and terminology for designing the emerging composition.
Chapter 9 is a rumination on how to think about one's own compositions in relationship to the grand tradition that precedes us.