Previous books on ko have been so bad that saying non-existent would be more honourable. If you are a kyu player and just look for the "first" ko book ever, don't hesitate - buy it! On the other hand, what is the absolute quality of its contents?
The book's first third contains theory chapters: Every chapter introduces one concept in general and gives examples. The remaining two thirds are filled by 122 problems and 11 professional games. Their introduction is a literary piece of art but also serves as an excuse for discussing too little theory. The problems are for different ranks up to 3d, also ask for reasons, numbers of ko threats, etc. and so are explained more interestingly than an ordinary problem book would do. Part of the game commentary is actually really good while other parts are not more special than the separate problems. For the joy of the reviewer, also a rules incident is not missing but otherwise the rules explanations in the book are factually weak. The selection of examples in the theory chapters has often been too efficient: Instead of inventing the authors' own positions, such invented by others are cited, even where this would hardly have been necessary.
The theory chapters include
Although the list of four reasons to fight a ko is useful, the claim that almost all ko fights belonged to the categories is wrong: E.g., the endgame kos are not included. Pretended simplification can be found everywhere; so the book is hardly useful for dan players. Discussion of the shape ko types and of some functional ko types is as weak as it is too short. Values may be incorrect by about a point. Important concepts like, e.g., double threats are missing entirely. Approach or stage kos are analysed elegantly by the number of the ko loser's tenuki stones while one misses an explanation of the value of one excess stone.
The book's greater strength is introducing concepts at all and with rough guidelines for players not having known them before. For this purpose, the general concepts are described well enough. Besides one should be greatful that the book starts with the very important values of kos and threats - a topic, when related to ko, found so far mostly only in the internet. However, the reader should not expect too much - the given explanations are short to very short. While the book enters a gap in literature, it does not even attempt to come close to filling it.
Date: 02 Mar 2008