Changes in climate will alter natural processes in the environment, and it is expected that one consequence will be that salinization processes in salt-affected soils will be modified. An expert system, called S ALINEXP, was developed to assist the prediction of climate change induced salinization processes in salt-affected soils. The paper discusses the considerations used in the construction of the knowledge base, the state and objective variables, and the rules and decision making processes of the system. Results of a scenario analysis are also discussed when the system is applied to the Middle-Tisza Region of Hungary.