How CLOCKSS Works: Ensuring Long-term Access to Digital Content Adam Chesler 07 Jan 2008 04:10 UTC

How CLOCKSS Works: Ensuring Long-term Access to Digital Content

The CLOCKSS initiative is a partnership of libraries and publishers committed to ensuring long-term access to scholarly work in digital format.  As more and more content moves online, there is growing concern that this digital content may not always be available. CLOCKSS addresses this problem by creating a secure, multi-sited archive of web-published content that can be tapped into as necessary to provide ongoing access to researchers worldwide *for free*.

There are many ways digital content may become unavailable, including when a publisher chooses to retire a journal.  SAGE Publications, a CLOCKSS partner, recently announced that it would discontinue online access to its journal, "Graft: Organ and Cell Transplantation."  This represents an opportunity to demonstrate how CLOCKSS responds to a "trigger event."

Building on the recent Pilot project, CLOCKSS publishers will feed digital content, including the journal "Graft," into a distributed archive housed at seven sites around the globe.  When content ceases to be available, for whatever reason, and for an agreed lapse of time, a "trigger event" is judged by the CLOCKSS Board to have occurred.  Content stored in the archive is released to designated delivery platforms or hosts, ensuring unrestricted access to research literature that might otherwise have been lost.

The current CLOCKSS Board, established in 2005 to oversee the Pilot, includes executives from the world's leading publishers -- responsible for about 60% of journal content currently online -- and representatives from six leading libraries and OCLC.  Together they have developed a network of geographically-diverse CLOCKSS archive sites.  The sites maintain "CLOCKSS boxes," computers with storage to hold and preserve multiple copies of content from the participating publishers.  These geographically-dispersed copies are under different administrative control and are continually and automatically audited against one another. These copies remain "dark," hidden and unavailable for use, until a trigger event leads the CLOCKSS Board to "light up" the content and restore access to it again.

Negotiations are underway to expand the CLOCKSS archive network to 12 to 15 libraries.  CLOCKSS is actively recruiting additional publishers and libraries to join the initiative.  For information on joining CLOCKSS, please visit <>  or contact <> .

In June 2007 CLOCKSS was the inaugural winner of the Association for Library Collections & Technical Services (ALCTS) Outstanding Collaboration Citation, which recognizes and encourages collaborative problem-solving efforts in the areas of acquisition, access, management, preservation or archiving of library materials.  The ALCTS is a division of the American Library Association.

The CLOCKSS initiative is funded by participating publishers and library organizations, as well as by a grant from the National Digital Information Infrastructure and Preservation Program (NDIIPP) via the U.S. Library of Congress.  The grant is intended to finance CLOCKSS through a mixture of ingest fees from publishers and revenue from an endowment raised from voluntary contributions over the next five years.  The need to secure long-term sustainable funding for CLOCKSS will be one of the key strategic issues facing the Board in 2008.

For more information about the CLOCKSS initiative, please visit <>  or contact <>  for information.  See also, <>  for background information.

Participating Libraries in Pilot:

Indiana University, New York Public Library, OCLC, Rice University, Stanford University, University of Edinburgh, and University of Virginia

Participating Publishers in Pilot:

American Chemical Society, American Medical Association, American Physiological Society, Elsevier, IOP Publishing, Nature Publishing Group, Oxford University Press, SAGE Publications, Springer, Taylor & Francis, and Wiley-Blackwell

Adam Chesler
Assistant Director, Library Relations and Customer Service
American Chemical Society
1155 16th Street NW
Washington, DC 20036

Office Telephone:  (202) 872-6183
Mobile Telephone:  (202) 465-0057
E-Mail:    <>

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