Unlike the first reviewer who gave this book 1 star, this is actually an excellent book showing designs taken from one of the many complex arts and crafts traditions of Japan. These are actual designs from stencils, which were carefully cut from mulberry paper and used for printing designs on cloth.The stencils are called katagami. Some of these are still being made, and by the fine traditional craftsmen of Japan working with simple, traditional tools to produce amazing patterns. The first reviewer has not bothered to look carefully into Japanese art forms, and so is, I believe speaking from ignorance. Not a book for tatoo designs, granted, but I think most people who would like design references from a somewhat obscure Japanese art tradition would find this book of interest. If you'd like more detail on the art tradition of stencil cutting or carving, you might want to look at
"Carved Paper: The Art of the Japanese Stencil." You can also see an example with some explanations here: http://www.sohe.wisc.edu/depts/hlatc/pixelsexhibit/katagami.html
Although these stencils were/are made for the purpose of dyeing cloth, they can be considered artforms in their own right. (I own a couple of these.) The Dover book is a nice reference.