In the case of an nuclear or radiological incident with several patients exposed to ionising radiation, diagnostic and therapeutic decisions are time critical. Since results of a physical dose-reconstruction but also from methods for biodosimetry (e.g. dicentrics) will be available after several days or even weeks, clinical signs and symptoms of the radiation exposed patients may be the only available basis for estimation of radiation effects and prediction of the clinical course. The METREPOL-System is based on indicators of effect and repair to manage radiation accident victims considering multi-organ involvement and potential treatment options.