To any library with an electronic collection of any significance, the OpenURL link resolver has (or should) become an indispensable service for helping its users retrieve full text from citations. Although they are a relatively new technology (in library terms, at any rate), link resolvers arguably have become as important as the OPAC; they locate articles from A&I databases, strengthen the role of interlibrary loan, and enable metasearch. Since they are the glue that binds many disparate services together, link resolvers are quite difficult to shop for. This article will help guide you on the things you should be looking for when purchasing a link resolver.