2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/44465We review the renormalization group method applied to non-equilibrium dynamics by tracing the way how the hydrodynamic equations can be derived as reduced dynamics of the Boltzmann equation as a typical example.Talk presented at YITP meeting "Non-equilibrium dynamics in QCD phase transitions", Feb. 22 - 24, 2005, YITP, Kyoto. To be published in the proceedings. Five pages with no figuresHigh Energy Physics - Phenomenologytext