The reuse of previous design knowledge is a potentially important way to improve design efficiency. In practice, however, design reuse is plagued with difficulties, including those associated with the indexing, retrieval, understanding and modification of prior design knowledge. We propose that such difficulties can be ameliorated by employing insights deriving from design-rationale research concerning how best to represent and retrieve design information. We illustrate these insights by describing the development of a design-reuse system that maximizes the benefits of rationale capture and information retrieval whilst minimising the costs to the designer that might arise from disruption to natural design work.