A collection of six of the nine traditions taught within the Bujinkan organization, Masaaki Hatsumi lists most of the unarmed fighting kata found there of. The traditions include Gyokko-ryu Kosshijutsu, Koto-ryu Koppojutsu, Togakure-ryu Ninpo Taijutsu, Takagi Yoshin-ryu Jutaijutsu, Kukishinden-ryu Dakentaijutsu, and Shinden Fudo-ryu Dakentaijutsu.
My own copy of this has been worn out until it is difficult to pull off the shelf without it it falling apart.
Each chapter begins with paragraphs of Hatsumi's writings and philosophies regarding the related material, borrowing from the nine traditions and exemplifying the work that his teacher, Takamatsu Toshitsugu put in to integrate them all. Much of the content is intersected with various double and triple entendre, which is unfortunately lost in the English translations.
The overall translations is useful to the average Bujinkan practitioner, however there are errors when comparing the English and Japanese sections (a with many of Hatsumi's publications through Kodansha International, the book concludes with a Japanese transcription of the manuscript), sometimes with entire paragraphs and charts missing from the English translations. Sometimes simple kanji are confused (右 "right" and 左 "left" being swapped in a technique description). But honestly I think that Hatsumi would jsut shrug that off and say that it's not important.
I have been re-translating the whole book for a few years now, and it has tremendously helped my Japanese understanding, as well as filled out several of my note books. I recommend a similar approach to anyone both studying the Bujinkan's traditions as well as studying Japanese.