Published by the American Geophysical Union as part of the Geodynamics Series, Volume 21. The Soviet Union includes about one-seventh of the land area on Earth, and Soviet geologists most likely number more than one-seventh of the world"s geologists. Moreover, Soviet geologists are probably considerably more familiar with the geological literature of North America and western Europe than the geologists from those regions are with the literature of the Soviet Union.General summaries of Soviet geology in English have been available, but they are fairly old by now and do not reflect the more recent theoretical developments in the science, in particular the plate-tectonic paradigm. Zonenshain, Kuzmin, and Natapov have mastered that paradigm and are thoroughly familiar with its ramifications; between them they are also familiar with most parts of their vast country.