"Left-Wing" Communism: An Infantile Disorder (Russian: Детская болезнь "левизны" в коммунизме, Detskaya Bolezn' "Levizny" v Kommunizme) is a work by Vladimir Lenin attacking assorted critics of the Bolsheviks who claimed positions to their left. Most of these critics were proponents of ideologies later described as left communism.
The book was written in 1920 and published in Russian, German, English and French later in the year. A copy was then distributed to each delegate at the 2nd World Congress of the Comintern, several of whom were mentioned by Lenin in the work.
Lenin's manuscript was subtitled "A Popular Exposition of Marxist Strategy and Tactics", but this was not applied to any edition brought out during his lifetime.
The book is divided into ten chapters and an appendix.
Lenin points out that the Russian Revolution has considerable international significance, and criticises the leaders of the Second International, including Karl Kautsky, for failing to recognize the international relevance of Soviet power as a revolutionary model. To illustrate their move away from revolutionary politics, he supplies a quote from a 1902 work of Kautsky which concludes that "Western Europe is becoming a bulwark of reaction and absolutism in Russia."
Lenin asserts that in a war against the bourgeoisie, "iron discipline" is an "essential condition". He then describes the circumstances which led the Bolsheviks to this conclusion in their success at taking state power in Russia.
The third chapter divides the history of Bolshevism into the "years of preparation of the revolution" (1903–05), the "years of revolution" (1905–07), the "years of reaction" (1907–10), the "years of rise" (1910–14), the "first imperialist world war" (1914–17) and the "second revolution in Russia". He describes the changing circumstances for revolutionaries in Russia and the reaction of the Bolsheviks to them.