A common requirement when developing web sites is a reduced time to operation. Reuse of conceptual views and code components from exiting operational sites is a key to reduce the development time and risks while improving the quality of the site under development.

In this paper we outline an approach to reuse of existing sites by means of cloning and adaptations. The starting point is a repository of conceptual views of existing web sites, corresponding code components, and traceability links between the conceptual views and the code. We use UML diagrams to express the conceptual views. The requirement of a new site are matched against the conceptual models in the repository to identify reuse candidates, and the traceability links are then exploited to isolate the corresponding code components and to devise any needed adaptations.