I'd agree with Victor. There are millions of aikido books around now, but at the time this was a very special book. I travelled 200 miles to central London to a special Japanese/English book store near St. Pauls to purchase my copy and felt it was well worth it. The diagrams were ground breaking (and this format is still used regualrly). The descriptions of the techniques are also short but very informative and readable by people with little understanding of aikido. The history is brief, but there were no books on aikido history around at the time. It was also the closest thing to a 'comprehensive text' at the time. Even now I would say it is a useful contribution to an aikido book collection, although not necessarily my first choice anymore. Despite this it is better than the majority of aikido books which I consider to be on the whole quite poor (Gozo Shioda's books excepted).