The European Validation of the Integral Code ASTEC (EVITA) involves 19 partners from eight European countries plus JRC. It started in February 2000 and ended in July 2003. The main objective is to distribute the severe accident integral code Accident Source Term Evaluation Code (ASTEC), jointly developed by “Institut de radioprotection et de surete nucleaire” (IRSN, France) and “Gesellschaft fur Anlagenund Reaktorsicherheit” (GRS, Germany), to European partners in order to apply the validation strategy issued from the VASA project (4 European Community Framework Programme). Severe accident management (SAM) measures are currently being developed and implemented at Nuclear Power Plants (NPP) worldwide in order to prevent or to mitigate severe accidents. This needs a deep understanding of processes leading to severe accidents and of phenomena related to them. As greater account of severe accident measures is taken in the regulation of plants, there will be the need to show a greater degree of validation of codes and a better understanding of uncertainties and their impact on plant evaluations. The EVITA evaluation of ASTEC code capabilities and the corresponding feedback towards the code development is an important step towards the intention to provide end-users (like utilities, vendors and licensing authorities) with a well validated European integral code for the simulation of severe accidents in NPPs.