  Modelling Quark-Gluon Plasma formation and decay in high energy heavy ion
reactions is presented in a framework of a multi-module setup. The collective
features, governing the equlibrated fluid dynamical stages of the model are
emphasized. Flow effects formed from the initial conditions are discussed.
Particular attention is given to the improvement of the final hadronization and
freeze-out part of the reaction which has strong effects on the observables.
