Design patterns have proved very helpful in encapsulating the knowledge required for solving design related problems, and have found their way into the CHI domain. Many interface patterns can be formalised and expressed via UML models, which provides the opportunity to incorporate such patterns into CASE tools in order to assist user interface designers. This paper presents an implemented tool-based approach for the discovery of an appropriate set of design patterns applicable to a high-level model of the system. The tool accepts a UML model of the system and presents a set of interface design patterns that can be used to create an effective implementation. The tool is aimed at providing designers with guidance as to which successful design approaches are potentially appropriate for a new interactive system, acting as a supportive aid to the design process. The use of high-level modelling approaches allows designers to focus on the interactions and nature of their systems, rather than on the technologically-driven details.