ISO 18626 Interlibrary Loan Transactions

ISO TC46/SC4/WG14 Interlibrary Loan Transactions



Last update: 7 March 2019


News and information about implementation of the new standard for ILL:

- ISO 18626 Information and documentation - Interlibrary Loan Transactions



ISO 18626 Information and documentation - Interlibrary Loan Transactions will at first supplement and eventually succeed ISO 10160, ISO 10161-1 and ISO 10161-2. Unlike its predecessor, ISO 18626 is well suited to the modern, Web-based technological environment which is based on XML and Web services. Another important difference between the two standards is that while the old standard is based on a 1980s model of ILL transactions, its successor is based on and supports much simpler exchange of transactions.


The standard includes three simple messages: a request, a supplying library message and a requesting library message and confirmations messages for this. The protocol is stateless, which means that there will be no need to maintain the interconnected state tables in the client and server applications (and the connections to the state tables in applications behind them). It is expected that the new ILL protocol will be much easier to implement than the old one, while still retaining the essential functionality of its predecessor.


ISO 18626 is the first part of a more general strategic initiative to standardize resource sharing in ISO/TC46/SC4 Technical Interoperability.



Open Codes

The list of open codes is prescribed in the standard, but will be continuous extended.



The guidelines and use cases is prescribed in the standard, but will be continuous extended.



XML Schema

The actual XML schema for ISO 18626.











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ISO Members:







Convener Leif Andresen

ISO TC46/SC4/SC14 Interlibrary Loan Transactions


Editors of ISO 18626: Leif Andresen (The Royal Library, Denmark), Clare Mackeigan (OCLC Relais), and Ed Davidson (OCLC).


Members WG14


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March 7, 2019

ISO 18626 survey

As interest grows in ISO 18626 as a means to improve interoperability between systems that support ILL and resource sharing , the editors of the standard would like to get a better overview of what is happening in the community. A survey has been published to assist in gathering this information as well as understanding where changes or improvements in the standard are needed and in the level of interest in forming an implementer's group to work through implementation questions and issues. If you are actively planning for the implementation of ISO 18626 or considering doing so, please take a few minutes to complete the survey by April 15.

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