Overall, the book's structure is straightforward and easy to follow, facilitating the ease with which it can be used as a reference. This volume, however, can also comfortably be read cover to cover, as the writing style is very clear, with almost seamless transitions from one topic to another. It will certainly serve as an invaluable resource for anyone interested in the structure or dynamics of geographic ranges, as it greatly surpasses previous works on these topics in its thoroughness and clarity. It should do much to advance the field of biogeography, and to provide a context for conservation in a world where the distribution, size, and internal structure of geographic ranges are ever changing.