In this article we discuss an alternative approach, using a knowledge-based expert system, to the design of offshore structures. The implemented expert system can assist engineers in the preliminary design of shallow-water offshore jacket structures. The system is capable of configuring and automatically generating the basic structural model of a fixed template-type steel jacket structure for analysis and design. In addition, the system allows the user to alter any of the inferred recommendations. The system is called IPDOJS (Interactive Preliminary Design of Offshore Jacket Structures).