Attempts to link clinical information systems to on-line information resources date back over a decade. The World Wide Web presents new opportunities to create such links, which we refer to as "infobuttons". This capability is partly due to the ease with which a link (called a Uniform Resource Locator, or URL) in one Web-based system can take users to another Web-based system, and partly due to the proliferation of high-quality Web-based resources. Typically, contextual information from the clinical system (such as patient data) is passed to a search engine that is evoked and, in turn, presents search results to the user. Impediments to infobutton development include customized programming to pass context information to the information resource, lack of standards for types and values of context information, variability of search engine interfaces, and a lack of understanding of clinicians' information needs. We are addressing these limitations with an Infobutton Manager (IM) that provides a standardized interface for matching user contexts to information resources.