The potential application of case-based reasoning (CBR) in design support is illustrated through examples drawn from research at the University of Paisley, demonstrating the suitability of CBR for different aspects of design, different problem areas, and different design goals. A quality advisory system has been developed for the early stages of mechanical engineering design, the aim of which is to provide quality advice in a variant design situation. In the domain of software engineering CBR has been applied to advise on which metrics are appropriate fora assessing the quality of the software currently under design. The system integrates CBR with concepts from quality function deployment (QFD) and incorporates a case library holding past software quality histories. CBR has been applied in support of conceptual design: to capture detailed design histories by monitoring designer actions, and thereby support design reuse through the evaluation of designs, through the provision of query, browsing and replay facilities. The resulting system is aimed to support the design of safety critical systems, by assisting in the construction of safety arguments, and cooperative design.