The interior of the Earth is largely inaccessible to direct observation; the deepest drill holes are only .1% of the Earth's radius. One might call it the undiscovered country. The mysteries of the interior have spanned a great deal of scientific and non-scientific literature. Most of what we know about the interior comes from seismological observations, our most informative probe of the deep Earth. Seismology reveals the variations of seismic velocities both laterally and at depth. Converting that information into knowledge about the structure, composition, and dynamical state of the Earth's interior requires other disciplines, high-pressure mineral physics, and geodynamics in the broadest sense. Without mineral physics, it would be impossible to properly translate the seismic information into knowledge of composition and dynamics. Shun Karato, a leader in mineral physics who is now at Yale University, provides the proper context to use a great variety of mineral physics data for interpreting both seismological observations and their relation to the dynamics of the interior. As such, The Dynamic Structure of the Deep Earthc An Interdisciplinary Approach is a welcome and unique addition to books on the geophysics of the Earth, as I can recall no other that combines a focus on the deep Earth with equal play given to several different disciplines. It is not a textbook, although it could be used as background reading in a graduate-level seminar. The book was originally published in Japanese in 2000 by the University of Tokyo Press; it was translated and updated for the current English edition.