The PREMIS maintenance activity is responsible for maintaining, supporting, and coordinating future revisions to the PREMIS data dictionary. The Preservation Metadata: Implementation Strategies Working Group, convened by OCLC and RLG, initially developed the PREMIS data dictionary as a specification with the goal of creating an implementable set of "core" preservation metadata elements, with broad applicability within the digital community. a supporting xml schema allows for implementation of element set and is maintained in network development marc standards office library congress.