If you need a history of each pottery manufacturer, this book is not for you. The author cuts right to the chase and gives us what we need -- an authoritative directory of makers' marks. He provides a photograph of the mark and right next to it an illustration of a typical product of the factory. Although in some cases experts might quibble about what is "typical" the result is an incredible cumulative reference source. Dating has been derived from Kovel, Lehner and other reputable sources. The marks are arranged alphabetically, which is about as user-friendly as this sort of tool gets. Add to this good indices, and we have a reference tool that no museum, collector or dealer should be ashamed to own.