Synthesis anarchism, synthesist anarchism, synthesism or synthesis federations is a form of anarchist organization that seeks diversity upon its participants and tries to join anarchists of different tendencies into a single federation. In the 1920s, this form found as its main proponents the anarcho-communists Voline and Sébastien Faure, bringing together anarchists of three main tendencies, namely individualist anarchism, anarchist communism and anarcho-syndicalism. It is the main principle behind the anarchist federations grouped around the contemporary global International of Anarchist Federations.