The Revolution Betrayed: What is the Soviet Union and Where is it Going? (Russian: Преданная революция: Что такое СССР и куда он идет?) is a book published in 1936 by the former Soviet leader Leon Trotsky.
The book criticized the Soviet Union's actions and development following the death of Vladimir Lenin in 1924. The book is regarded as Trotsky's primary work dealing with the nature of Stalinism and socialist democracy. The book was written by Trotsky during his exile in Norway and was originally translated into Spanish by Victor Serge. The most widely available English translation is by Max Eastman.