Democratic centralism is a political concept referring to the governance of political parties and groups. The democratic aspect of this methodology describes the freedom of members of the political party to discuss and debate matters of policy and direction, but once the decision of the party is made by majority vote, all members are expected to follow that decision unquestioningly in public. This latter aspect represents the centralism.

It is generally regarded as being an element of Leninism, and the term is sometimes used as a synonym for Leninist policy inside a political party. The term was also adopted by Stalin in his famous book on Leninism, and it is from this work that many commentaries derive.

As Lenin described it, democratic centralism consisted of "freedom of discussion and criticism, unity of action". The doctrine of democratic centralism served as one of the sources of the split between the Bolsheviks and the Mensheviks. The Mensheviks supported a looser party discipline, within the Russian Social Democratic Labor Party in 1903.

In Lenin's lifetime, democratic centralism was generally viewed as a set of principles for the organising of a revolutionary workers' party. Lenin's model for such a party, which he repeatedly discussed as being democratic centralist, was the German Social Democratic Party. Similarly, Lenin's theoretical model of democratic centralism was adapted from the work of Karl Kautsky, as he makes clear in his pamphlet What is to Be Done? [1], which is popularly seen as the founding text of democratic centralism.

After the successful consolidation of power by the Communist Party following the Russian Revolution and the Russian Civil War, the Bolshevik leadership instituted an ostensibly "temporary" ban on factions within the party in 1921, by using the very mechanism of "democratic centralism" . This precipitated the end of the "democratic" element of democratic centralism within the party membership, and with the rise of Stalin to a position of absolute power within the party (and the Soviet Union), there was no freedom of discussion within the party, except by members of the ruling Politburo.

These developments have led some observers to question whether the democratic aspect of democratic centralism can be maintained over time. The issue remains controversial today.