Working together through the IMLS-grant funded Copyright Review Management System (CRMS), nineteen libraries collaborate daily in identifying public domain volumes held in the HathiTrust Digital Library. Led and coordinated by the University of Michigan, trained CRMS reviewers assess and determine the copyright status of digital books. When a work has entered the public domain, CRMS reviewers facilitate access to digital collections and expand the universe of freely-available online library resources. Collectively, CRMS reviewers have performed over 312,631 copyright determinations for US-published books, and an additional 105,977 determinations for books published in Canada, Australia, and the United Kingdom. What does the CRMS project mean and how does it inform standards for a responsible search for the public domain? Kristina Eden, copyright instruction librarian at the University of Michigan, and Melissa Levine, principal investigator for the CRMS projects, will:" provide an overview of the project" talk about the successes and challenges of CRMS; and " explain why these efforts are critical to fulfilling the promise of the public domain.