Over the past three decades, modelling packages for chemical processes have become more advanced and widely used. For example, equation-oriented dynamic simulators such as gPROMS and SpeedUp (Pantelides and Barton(1)), are useful for simulating plantwide processes as well as unit operations. However, they rely on the user being proficient in modelling. A useful next step would be the integration of some knowledge into the formation of the process models. This would lead to the design engineers having a library of knowledge to check on first, much as an expert engineer uses their past experiences to help guide them through a design. If this could be incorporated into a modelling interface this would greatly help the design engineer, especially when tackling problems in areas in which they have little, or no experience. This paper describes the design of an intelligent modelling interface that incorporates a knowledge base using some form of apriori case library and recall facility. The interface also incorporates an automatic input file generation stage. At present, the user can: specify a single unit operation problem to search for, retrieve similar cases from the database, specify their solution in the database based on past cases and experience, and then automatically generate an input file for the gPROMS simulator (Clak(2)). A tubular reactor example is used to illustrate how the system works.