||Managing and reusing knowledge in architecture, engineering and constructionfirms can lead to greater competitive advantage, improved designs, and moreeffective management of constructed facilities. We define design knowledge reuseas the reuse of previously designed buildings, building subsystems, or buildingcomponents, as well as the knowledge and expertise ingrained in these previousdesigns. This paper introduces the notion of knowledge in context. We argue thatin order for knowledge to be reusable, the user should be able to see the context inwhich this knowledge was originally created and interact with this rich content.We call a repository of such knowledge in context the corporate memory. Wedescribe empirical observations of designers reusing knowledge from theirpersonal design experiences. Based on these observations, we formalize two keyactivities in the process of knowledge reuse: finding reusable items andunderstanding these items in context. We formalize six degrees of exploration thatlead to understanding. We describe a prototype knowledge management system,CoMem (Corporate Memory), that supports these activities. CoMem isdistinguished from the document-centric state-of-practice solutions by its approachof "overview first, zoom and filter, and then details-on-demand."