The main topic of the article is the mechanisms and models of self-organization of the deputies of the Third State Duma of the Russian Empire. We examine how Duma factions were founded, who were their leaders, and what organizational structures were used by deputies to coordinate their work and consolidate factions in fundamentally new conditions of parliamentary activity. The author analyzes each of the 14 factions that existed during different periods of the third convocation. Three models of deputy organization are identified and their characteristics are analysed. None of the models showed a decisive superiority in terms of discipline or in the effectiveness of achieving long-term political goals. Nevertheless, the models themselves allowed the factions to organize their work in the way that was most preferable to them.