Rebecca Guenther has over 35 years of experience in national libraries, primarily working on metadata standards. Most of that time was at the Library of Congress developing national and international metadata standards, including MARC 21, MODS, PREMIS, METS, and ISO language codes. She has served on numerous national and international standards committees, several as chair, has published widely in professional literature, and has given many workshops and presentations. She is currently a consultant on metadata issues based in New York. Some of her previous and current consultancies include the Library of Congress (working on BIBFRAME and PREMIS), the National Book Foundation, the New York Art Resources Consortium, the Academy of Motion Picture Arts and Sciences, and the Metropolitan New York Library Council. She teaches metadata at NYU’s Moving Image Archiving and Preservation Program, Pratt’s School of Information and Library Science and several classes for Lyrasis. She continues to serve on the PREMIS Editorial Committee, MODS Editorial Committee and PB Core Advisory Subcommittee.