May 24, 2022

Special Collections: New RLUK Report Reveals the Growing Problem of Hidden Collections in UK

From a Research Libraries UK (RLUK) News Release:

Some 13 million volumes of material remain uncatalogued in libraries across the UK, according to a recent report.

‘Hidden Collections’, undertaken in partnership with the London Library,  is the first of three reports to be published by RLUK as part of its Unique and Distinctive Collections (UDC) strategic strand that will provide a comprehensive review of the state, and nature, of special collections in the UK. The report surveyed a wide range of libraries across the sector including university, museum and national libraries with collections totalling over 75 million items.


Perhaps not surprisingly, non-traditional formats are heavily represented in backlogs as librarians are prioritising material that can be easily catalogued over that which requires specialist skills and expertise such as foreign language, cartographic and archival material. Some of the libraries surveyed admitted that their retrospective cataloguing or conversion projects have had to be halted in part or entirely due to a lack of funding, a situation exacerbated by the continual influx of modern material that is only adding to the overall backlog.

The report recommends the establishment of a national register of hidden collections that would allow collection holders to self-document their uncatalogued material, leading to a more coherent awareness of the scale of the backlogs nationwide and encouraging greater opportunity for collaborative and cross-sectoral digital initiatives and funding applications.

Another recommendation put forward in the report is the creation and utilisation of a freely available cataloguing tool, based perhaps on RLUK metadata and Copac, which would be especially beneficial to smaller-scale collection holders in making their collections discoverable online.


The second report in the UDC strand has been undertaken in collaboration with OCLC and will be released in January 2013. The final Promoting Unique And Distinctive Collections report is scheduled for release in the spring of 2013.

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.

Direct to Full Text Report (57 pages; PDF)

Read the Complete News Release

About Gary Price

Gary Price ( is a librarian, writer, consultant, and frequent conference speaker based in the Washington D.C. metro area. Before launching INFOdocket, Price and Shirl Kennedy were the founders and senior editors at ResourceShelf and DocuTicker for 10 years. From 2006-2009 he was Director of Online Information Services at, and is currently a contributing editor at Search Engine Land.