The Linked Data for Libraries (LD4L) team, consisting of librarians, ontologists, metadata experts, and developers from Cornell, Harvard, and Stanford libraries with support from the Andrew W. Mellon Foundation, has recently completed its first two years of work on adapting and developing Linked Open Data standards for describing and sharing information about scholarly information resources. In this presentation we will: 1) describe how to search, access, and use the Linked Open Data created by the project, representing some 29 million scholarly information resources cataloged by the three partner institutions; 2) describe the follow-on work of two closely related projects – LD4L Labs is creating tools to support original cataloging of scholarly information resources using linked data, as well as tools to support using linked data to organize, annotate, visualize, browse, and discover these resources, and LD4P (Linked Data for metadata Production) is a partnership of Stanford, Columbia, Cornell, Princeton, Harvard, and the Library of Congress to do original and copy cataloging of a wide range of collections and materials; and 3) draw on the use cases and examples embodied in this work to discuss some of the challenges and opportunities they pose for open repositories.