[en] The worked implemented within the framework of the project was directed towards understanding the conceptual basis for the organization of intervention strategies after the accident at the Chernobyl nuclear station. Based on the situation in regions of Belarus, Russia and Ukraine that suffered the consequences of the accident, this project was directed towards the provision of support the decision makers. The work will assist in the choice of proper strategies to protect the population from the effects of environmental contamination, taking into account the available resources. The experience gained, both of the problems of decision aiding in this context and their solution, will be of use in post-emergency planning for possible future accident situations. At present there are several prototype computer systems which provide the following: access to a wide range of information gathered after the accident at the Chernobyl nuclear station in the CIS; support in complex evaluations of the post-accident situation for a wide range of parameters; analysis and forecast of how the situation may develop using mathematical models and algorithms; support in choosing strategies at each level of decision making taking into account the possibilities of applying a wide range of countermeasures; exploration of multifactor interdependence and the consequences of resource and other limits; the integration of experience in social and psychological factors into the decision making process. Calculations made by the computer modules are based on actual data from contaminated territories including structure of soils, age/sex structure of the population, and dietary habits. At present the models for the calculation of doses and radionuclide migration in soil are specific to the regions contaminated after the Chernobyl accident. They m based on a large amount of experimental data ranging from whole body measurements of the population to data about radionuclide transfer from soils to plants, milk, and meat. A risk module has been developed which includes a database d demographic data on health protection for different territories, and which can calculate risk for any population structure. It can be used for risk estimation for different age groups in any region for which data is provided. A module on indirect countermeasures has been developed to assist in the selection of counter-measures that will improve conditions for a population that inhabits a contaminated area, in a way that is distinct from a direct reduction in the effective contamination level of the environment and its products. These types of countermeasure can be taken both as separate actions or in combination with direct countermeasures to increase the efficiency of the latter. The tools and interfaces developed within JSP2 enable the decision maker to estimate consequences and analyze the post-emergency situation according to his own criteria and in a user-friendly manner. The available analyses include: forecast calculations (concerning the estimated contamination of agricultural products, the levels of doses in the local population and the associated radiation risks); the identification of the critical factors that influence the health nf the affected population; a simulation of human intervention taking into account the countermeasures chosen or a time ordered set of countermeasures; an estimation of the influence such factors as dose, risk, cost/benefit and time, etc. have on decisions. The results can be presented in the form of maps, diagrams, and tables. In this paper, work carried out on the development of computer based decision support systems for the post-emergency management of contaminated territories is discussed, together with possibilities for further development of such systems