Preserving the World's
Rarest Books

The Programme

Preserving the World’s Rarest Books is a new programme, sponsored by the Andrew W. Mellon Foundation of New York, which aims to put the analytical power of the Universal Short Title Catalogue (USTC) at the disposal of the world library community.

The USTC is an analytical database of books published throughout Europe before 1601. At present it comprises data on 364,000 items, represented in 1.5 million surviving copies. In June 2016 USTC coverage will be extended to 1650, doubling the size of the resource. Many of the books described in the USTC are extremely rare: around 30% survive in only one located copy. Using the resources of the USTC we can locate all of these apparently unique items and report these findings to the holding libraries.

The St Andrews-Mellon programme is intended to help libraries find the rarest books in their collection, a time consuming task for any individual collection. Participating libraries will be furnished by the USTC team will a list of all their early holdings, ranked according to rarity. Libraries are free to do with this information what they wish: participation in the programme imposes no obligations. But some of our early partners have indicated that they may use our information to shape digitization priorities; others may highlight unique items in forthcoming exhibitions or publications. The USTC stands ready to assist in efforts to publicise interesting discoveries; at the very least it will help libraries to a clearer understanding of especially precious (and certainly irreplaceable) items in their own collections.

How to Join

The USTC welcomes enquiries from any institution with early printed holdings. We are actively seeking a range of participating libraries: large and small, public and private. We are also keen to work with libraries and archives interested in knowing more about their printed holdings.

Our initial group of partners includes both university and municipal libraries, one distinguished specialist library and one national library: they are spread among six countries in Europe and North America. In the first three years of the programme we intend to recruit a total of up to fifty libraries.

Expressions of interest should be addressed to the programme director, Professor Andrew Pettegree ( or the Project Manager, Graeme Kemp (

A Selection of Our Current Partners

  • University of Tasmania Library
  • Gent, University Library
  • Aix, Bibliothèque Méjanes
  • Rennes Métropole
  • Trento, Biblioteca comunale
  • Dublin, Marsh’s Library
  • University College, Dublin
  • Somogyi Library, Hungary
  • Riga National Library
  • Universidade de Santiago de Compostela
  • De Paul University, Chicago
  • Houghton Library, Harvard
  • Morgan Library, New York
  • National Library of Medicine, Bethedsa
  • University of Pennsylvania
  • Vassar College