Computers increasingly collect, manage, and analyze data for scholarly research. Linked data gives libraries the ability to support this e-research, making it a powerful tool. Libraries are at a tipping point in adoption of linked data, and this issue of Library Technology Reports explores current research in linked open data, explaining concepts and pioneering services, such asFive building blocks of metadata—data model, content rules, metadata schema, data serialization, and data exchangeThree case studies—Europeana, Digital Public Library of America, and BIBFRAMEHow libraries, archives and museums are currently addressing such issues as metadata quality, open data and business models, cross community engagement, and implementation