The search tool, EBM Search, was programmed using Cold Fusion with a Microsoft SQL server database backend between February and August 2006. A rapid development process was employed, which focused on prototype development followed by an iterative feedback and modification process. The first iteration of the end-user search tool, developed in two weeks, provided the initial proof-of-concept and incorporated several design considerations. First, the search interface needed to be simple. Second, for practical and philosophical reasons, the team decided that providing a results screen that integrated results from all resources included in EBM Search into one single set was undesirable, in part, because the amount of development that would be required to manage a single results set was seen as unrealistic. More importantly, both clinical and library partners felt that an integrated results set was not optimal for enabling users to quickly select a resource at the appropriate level of evidence for their needs. Accordingly, the interface was organized around the evidence pyramid [16], a well-understood concept among local clinicians. Third, the search tool needed to incorporate librarian-designed search hedges to improve relevance for the target group, thereby reducing the need for expert searching skills from physicians. Fourth, EBM Search would use each resource's native interfaces for vocabulary mapping and relevance ranking, as these features were better developed in the individual resources than could be developed in this project. Finally, where feasible and meaningful, the number of results from each provider was displayed to enhance usability.