This is the most comprehensive book of lists of kings, queens, sultans, emperors, etc. that I have found in a single volume. It includes many dynasties that are rarely described except in advanced studies of individual countries or regions. The relationship of each ruler to his or her predecessor, if any, is given, which enables the reader to construct a rudimentary family tree. Ideally, I would have liked actual genealogical tables, but this would have produced a book of unmanageable size. The only drawback, though it is an irritating one, is the way the contents are arranged, which is strange and unnecessary. The book begins with a bibliography arranged by author's name in alphabetical order, followed by a Guide to Dynasties and States, a 150-page section giving brief descriptions and indicating where the related list(s) can be found. Then we have over 350 pages of lists. So if you are looking at a list of Mazyadids or Toccos you have to turn back to the Guide to find out more about them. If this interests you, and you want to read more, you have to work your way through the bibliography until you find the right book. It would be much more convenient if a short informative note was given at the beginning of each state section, and if the book or books used by the author could be named at the end of the section rather than having to be searched for. This criticism should not put anyone off buying the book. For anybody interested in this type of knowledge,(and in this field you are either an enthusiast or nothing), this is an essential addition to your library.