NISO RP-21-2013 are intended to assist information professionals involved in managing OpenURL linking environments in improving OpenURL linking by providing them with the tools necessary to measure OpenURL quality. The focus of the IOTA (Improving OpenURL Through Analytics) Working Group is the quality of the metadata that is passed to the link resolver from the OpenURL source. The quality of the data in the link resolver knowledge base itself is outside the scope of IOTA; this is being addressed through the NISO KBART initiative. Also outside of the scope is the quality of the linkages between link resolvers and full text content providers. (To our knowledge, this part of the OpenURL quality problem is not being addressed by any organized initiative.) This Recommended Practice is focusing on a specific genre of OpenURLs-those intended to provide access to journal articles. The information provided in this Recommended Practice could easily be adapted for other genres such as book and book chapters.