The Metadata Authority Description Schema (MADS) is an XML schema for an authority element set that may be used to provide metadata about agents (people, organizations), events, and terms (topics, geographics, genres, etc.). MADS serves as a companion to the Metadata Object Description Schema (MODS) to provide metadata about the authoritative entities used in MODS descriptions. The standard is maintained by the MODS/MADS Editorial Committee with the Network Development and MARC Standards Office of the Library of Congress and input from users.