View the report


The Hidden Collections report shares the findings of a 2010 survey carried out by Research Libraries UK (RLUK) and the London Library, with the technical and marketing assistance of Mimas.

The aim of the survey was to gather evidence about the ongoing need for retrospective cataloguing of UK collections, following on from the 2007 RIN report ‘Uncovering Hidden Resources survey.

It is now published in interim form, pending any further work to widen the scope to archives and manuscripts, as part of RLUK’s Unique and Distinctive Collections project.

77 responses were made to the survey (representing 75 separate institutions), including from 38 academic, seven public and 32 specialist libraries (including museums and subscription libraries, and the National Library of Scotland).

Key findings from the report:

  • Hidden collections remain an immense problem for UK libraries. Over 13 million volumes are uncatalogued in the libraries that responded, 18.5% of the total number of volumes held by those libraries. Over 4 million more (in a smaller number of libraries) have unsatisfactory catalogue records.
  • Some sectors have more hidden collections than others. Museums, public libraries and independent libraries have a higher proportion of collections which are invisible online.
  • However, while research libraries have better coverage of printed collections, their hidden archival collections often remain vast.
  • Modern material is being added to the backlogs. The presence of 21st century materials in the backlogs suggests that some libraries are unable to keep up even with current acquisitions.
  • Foreign language material and formats which require particular skills and expertise (maps, music, archives) are heavily represented.
  • There are serious problems in collating and comparing metrics for materials other than printed books.
  • Librarians are aware of the problem and are actively trying to tackle the backlogs; over 60% have retrospective cataloguing projects under way. However, the scale of the problem is often beyond individual institutions. Respondents support an online register of retrospective cataloguing and are interested in exploring national initiatives and technical solutions to bring this about.


Top image courtesy of University of Bristol Library, Special Collections