This review essay evaluates a lengthy new biography of the Chinese leader Mao Zedong and his impact on Sino-Soviet relations. The lead author of the book, Aleksandr Pantsov, is one of the foremost Russian experts on China and Soviet policy toward East Asia, and his coauthor, Steven I. Levine, is a distinguished scholar of the history of Communist China. The authors have amassed a wealth of primary evidence, especially from the former Soviet archives, and have produced a first-rate book.