Libraries around the world partner with us in order to discover the rarity of their collections. We work with them to identify their rarest books by comparing their holdings with the copies listed in the Universal Short Title Catalogue. Our partners are a number of different institutions, small and large, public and private. Learn how your library can partner with us!

The number next to each library represents which year they joined the project.

ARGENTINA

• Buenos Aires, National Library of Argentina (3)

AUSTRALIA

• Tasmania, University of Tasmania Library (1)

BELGIUM

• Antwerp, Hendrik Conscience Heritage Library (2)
• Antwerp, Museum Plantin-Moretus (2)
• Ghent, University of Ghent (1)
• Leuven, University of Leuven (2)
• Leuven, University of Leuven, Maurits Sabbe Library, the Library of the Faculty of Theology and Religious Studies (2)

CANADA

• Montreal, McGill University (3)
• Toronto, University of Toronto, Thomas Fisher Rare Book Library (2)
• Toronto, Centre for Reformation and Renaissance Studies (2)
• Vancouver, University of British Columbia (4)

DENMARK

• Copenhagen, Royal Danish Library (3)

FRANCE

• Aix, Bibliothèque Méjanes (1)
• Albi, Médiathèque Pierre-Amalric
• Paris, Bibliothèque interuniversitaire de santé (4)
• Paris, Institut Culturel Irlandais (2)
• Rennes, Métropole (1)
• Rennes, Bibliothèque Universaire (3)

GERMANY

• Berlin, German Historical Museum (2)
• Bremen, State and University Library  (2)
• Jena, Friedrich Schiller University and Thuringian State Library (3)

HUNGARY

• Szeged, Somogyi Library (2)

IRELAND

• Dublin, Chester Beatty Library (4)
• Dublin, Marsh’s Library (1)
• Dublin, University College (1)

ITALY

• Palermo, University of Palermo (3)
• Rome, Royal Netherlands Institute in Rome (4)
• Trent, Biblioteca comunale (1)
• Trent, Fondazione Biblioteca San Bernardino (3)

LATVIA

• Riga, National Library of Latvia (1)

NETHERLANDS

• Groningen, University of Groningen (2)
• The Hague, National Library of the Netherlands (2)
• The Hague, Museum Meermanno (3)
• Leeuwarden, Tresoar (2)

NEW ZEALAND

• Dunedin, University of Otago (3)

NORWAY

• Oslo, Cathedral School (3)

SPAIN

• Barcelona, University of Barcelona (4)
• Santiago de Compostela, University of Santiago de Compostela (1)

UNITED KINGDOM

• Armagh, Armagh Robinson Library (4)
• Blackburn, Central Library (3)
• Cambridge, University of Cambridge, Magdalene College, Old Library (4)
• Cambridge, University of Cambridge, Peterhouse Library (2)
• Cambridge, University of Cambridge, Samuel Pepys Library (4)
• Cambridge, University of Cambridge, Trinity Hall (2)
• Glasgow, University of Glasgow (2)
• London, Natural History Museum (4)
• London, University College London (4)
• Manchester, University of Manchester, John Rylands Library (2)
• Oxford, University of Oxford, Merton College (2)
• Oxford, University of Oxford, All Souls College, Codrington Library (2)
• Plymouth, Plymouth Museum Galleries Archive (4)
• St Andrews, University of St Andrews (2)

UNITED STATES OF AMERICA

• Connecticut, Yale University, Beinecke Rare Books & Manuscript Library (1)
• Florida, Florida State University (3)
• Illinois, DePaul University (1)
• Maryland, Johns Hopkins University, The Sheridan Libraries (2)
• Maryland, National Library of Medicine (1)
• Massachusetts, Harvard Botany Libraries (4)
• Massachusetts, Harvard Divinity School, Andover-Harvard Theological Library (2)
• Massachusetts, Harvard University, Houghton Library (1)
• New York, Grolier Club (3)
• New York, The Morgan Library & Museum (1)
• New York, Vassar College (1)
• Pennsylvania, University of Pennsylvania (1)
• Tennessee, University of Tennessee, Knoxville (4)
• Texas, Houston Baptist University (4)