The articles published in this volume were prepared as part of the inter-university research program on the regionalization of the Soviet Union for the needs of agriculture. The book forms part of the physical geography series Materials on the Regionalization of the USSR, which consists of two categories of works: monographs and concise explanatory texts accompanying regionalization maps. The articles included in this volume belong to the latter category. This volume contains regionalization materials relating to Krasnoyarsk Krai, the Yakut Autonomous Soviet Socialist Republic, and the Soviet Far East. The research was carried out by the Department of Physical Geography of the USSR at Moscow University, while the section on Krasnoyarsk Krai was prepared jointly with the Krasnoyarsk Pedagogical Institute. The regionalization studies of the above-mentioned areas are presented as independent articles. Although they were written according to a common outline, many aspects were not fully coordinated with one another. The editors consider the treatment of certain issues to remain debatable, for example, the division of Krasnoyarsk Krai into natural regions according to latitudinal zonal characteristics and zonal boundaries. It is possible that some territorial units classified as first-level regions in the Far East should instead be regarded as lower-level classification units. Because the authors differed in their understanding of the meaning and content of certain large regionalization units, the maps appended to the volume do not correspond completely with one another. Likewise, the descriptions of the delineated territorial units are not entirely comparable across the articles, reflecting differences in the degree of study of the various regions and in the nature of the source materials used. Nevertheless, the results of the physical-geographical regionalization studies of Siberia and the Far East presented in this volume are valuable in themselves and provide a foundation for the future development of a comprehensive scheme for the detailed regionalization of Siberia and the Far East for agricultural purposes. The synthesis and compilation of all available materials constitute one of the tasks of the next stage of the inter-university research program on the physical-geographical regionalization of the Soviet Union.