is an essential introductiion to the spiritual and perhaps more subtle side of the art. Although well presented and relatively lengthy in written content, it is a translation from the Japanese original. I found it must be approached with an open mind. 12 chapters cover various aspects such as the history of the art, ninjutsu in relation to other martial arts, taijutsu, and the spirit of Ninjutsu today as compared with the past. There are many short stories, often hiding clues to the true spirit of the art while they are also a welcome break in the overall structure allowing the reader to reflect more deeply on what they have read. It will be more useful to someone who has started practicing the art first. You should buy this after NInjutsu : History and Tradition.