In the paper some problems associated with the application of an expert system for a solution of some logistic problems will be considered. The Decision Support System (DSS) that condenses large amount of data is applied to support the managers who develop contracts to carry bulk cargos from the company warehouses to the customers. Because of the fact that some of the transportation contracts’ characteristics are imprecise or unpredictable, the authors suggested their descriptions on the basis of fuzzy logic and probability methods. The analytical power of the system will be supported by the fuzzy expert system enabling the choice of the appropriate customer orders to maximize the company’s profits. The considered decision-support system has been implemented and validated in the environment of the Exsys expert system.