A link resolver is a product that sits between a “source,” where a user begins the search process, and a “target,” where the user goes next. The “source” might be an abstracting and indexing database, an A-Z list of journal titles, an OPAC, or a footnote in an electronic full text article. If the source system can build a standards-compliant OpenURL containing metadata (typically bibliographic citation information) about the “object” the user is interested in, then a link resolver can generate a list (or menu) of relevant targets. Targets might be the electronic full text of the cited article (perhaps available from a provider other than the source where the user found the citation), or a document delivery request form, or a web-based service that will automatically reformat a bibliographic citation according to a specified style manual, suitable for pasting into the user’s bibliography.
From the end-user perspective, link resolvers work to determine the availability of information resources that are available within the library collection, and direct users towards the holding at their institution. Link resolvers effectively check if the institution is entitled to access (if it owns a copy or has a vaild license) a resource across the multiple products the institution subscribe to, and guides the end user through a process of linking to the resource.