Information and decision projects in the area of civil engineering are usually complex and heterogeneous. This, in turn, requires the use of IT solutions to support them. The selection of the appropriate models for data or knowledge representation, which are the information resources of such systems in connection with the selection of analytical and decision models, can be considered as one of the elements of the rationalization of engineering projects. The approach that takes account of the significant complexity and heterogeneity of problems is a system approach with the use of an objectoriented way of organizing data or knowledge. Not only does it ensure efficient modelling of information and decision processes in the field of engineering projects (also in crisis situations), due to the uniformity of the model approach, it also allows for maintaining the continuity of the implementation of complex processes of various specificity, e.g. the different levels of structuring or the randomness of partial problems.