Readex partners with renowned repositories, libraries, and historical societies to create authoritative digital collections. Among these institutions are the American Antiquarian Society, Center for Research Libraries, Library Company of Philadelphia, New-York Historical Society and Wisconsin Historical Society—each of which is briefly described below. Other major partners include the Dartmouth College Library, Historical Society of Pennsylvania, Kansas Historical Society, Library of Congress, University of Houston, University of Vermont Libraries, U.S. Senate Library, and others.
American Antiquarian Society 
Founded in 1812 as the country’s first national historical organization, the American Antiquarian Society is both a learned society and a major independent research library. On more than 25 miles of shelves it houses the largest and most accessible collection of books, pamphlets, broadsides, newspapers, periodicals, ephemera, and graphic arts material printed through 1876 in what is now the United States. Their holdings also include manuscripts and a substantial collection of secondary works, bibliographies, and other reference works related to all aspects of American history and culture before the twentieth century. The Society sponsors a broad range of programs for constituencies ranging from school children and their teachers through undergraduate and graduate students, postdoctoral scholars, creative and performing artists and writers, and the general public.
Center for Research Libraries 
The Center for Research Libraries (CRL) is an international consortium of university, college, and independent research libraries. Founded in 1949, CRL supports advanced research and teaching in the humanities, sciences, and social sciences by preserving and making available to scholars the primary source material critical to those disciplines. CRL acquires and preserves newspapers, journals, documents, archives, and other traditional and digital resources from a global network of sources. Most materials acquired are from outside the United States, and many are difficult to obtain or at-risk materials from six major world regions: Africa, the Middle East, Slavic and Eastern Europe, Southeast Asia, South Asia, and Latin America.
The Library Company of Philadelphia
The Library Company of Philadelphia is an independent research library specializing in American history and culture from the 17th through the 19th centuries. Founded in 1731 by Benjamin Franklin, the Library Company is America's oldest cultural institution and served as the Library of Congress from the Revolutionary War to 1800. The Library Company was the largest public library in America until the Civil War. Free and open to the public, the Library Company houses an extensive collection of rare books, manuscripts, broadsides, ephemera, prints, photographs, and works of art, as well as the second largest holding of early American imprints.
New-York Historical Society
The New-York Historical Society, one of America’s pre-eminent cultural institutions, is dedicated to fostering research, presenting history and art exhibitions, and public programs that reveal the dynamism of history and its influence on the world of today. Founded in 1804, New-York Historical is the oldest museum in New York City. It has a mission to explore the richly layered political, cultural and social history of New York City and State and the nation, and to serve as a national forum for the discussion of issues surrounding the making and meaning of history. New-York Historical’s Patricia D. Klingenstein Library is among the oldest and most distinguished in the United States, containing more than three million books, pamphlets, maps, newspapers, broadsides, manuscripts, prints, photographs and architectural drawings.
Wisconsin Historical Society 
Founded in 1846, the Wisconsin Historical Society is the oldest historical society in the United States to receive continuous public funding. The Society's world-class collections contain an extraordinary range of documents and information about American history, with nearly four million publications as well as 15 miles of shelving containing unpublished manuscripts, films, and other archival materials. The Society has one of the largest collections of historical newspapers in the United States, including perhaps the nation’s most complete collections of African American and Hispanic American newspapers. This stunning national treasure ranges from the 18th century to the present and serves the needs of researchers throughout the world.
