ISSN ICThe ISSN is one of the most widely recognized identifiers in the publishing and library world, providing a simple, compact code for uniquely identifying serial publications. Assigned to journals, magazines, newspapers, monographic series, and other continuing resources regardless of medium, the ISSN is essential infrastructure for bibliographic control, subscription management, and scholarly communication.
Background
The concept of a standard serial number emerged in the late 1960s and early 1970s as the volume of serial publications grew and libraries faced increasing difficulty in managing subscriptions and cataloging. The ISSN system was established through ISO 3297, first published in 1975, and the ISSN International Centre was founded in Paris in 1974 under an agreement between UNESCO and the French government. The centre coordinates a global network of national ISSN centres, each responsible for assigning ISSNs to serials published in their country. The system now encompasses over two million ISSN assignments.
Purpose & Scope
The ISSN serves as a unique identifier for serial publications -- continuing resources issued in successive parts. A separate ISSN is assigned to each distinct medium of a serial: a journal published both in print and online receives two different ISSNs. The Linking ISSN (ISSN-L), introduced in the 2007 revision of ISO 3297, provides a mechanism to collocate all media versions of the same serial under a single identifier.
The scope of ISSN assignment includes:
| Resource Type | Examples |
|---|---|
| Journals and periodicals | Nature, The Lancet, Library Quarterly |
| Newspapers | The New York Times, Le Monde |
| Monographic series | Lecture Notes in Computer Science |
| Annual reports and yearbooks | UNESCO Statistical Yearbook |
| Blogs and websites | Serials issued as web resources with continuing updates |
Key Elements / Properties
An ISSN is an eight-digit code, written as two groups of four digits separated by a hyphen:
| Component | Description |
|---|---|
| ISSN | Eight-digit identifier (e.g., 0317-8471) |
| Check digit | The final digit (may be 0-9 or X) validates the number using a modulus 11 algorithm |
| ISSN-L | A designated ISSN that serves as the linking identifier across media versions |
| Key title | A unique title assigned by the ISSN network, linked one-to-one with the ISSN |
The ISSN does not carry embedded meaning -- the digits are assigned sequentially and do not encode publisher, country, or subject information.
Serializations & Technical Formats
The ISSN itself is a simple numeric string. It appears in MARC records (field 022), in DOIs as part of journal-level identifiers, in OpenURL context objects, and in various library and publishing system databases. The ISSN International Register is the authoritative database and is accessible through the ISSN Portal. The ISSN-L mapping table, which links ISSNs for different media versions, is published as open data.
Governance & Maintenance
The ISSN system is governed by the ISSN International Centre, headquartered in Paris. The centre operates under the auspices of UNESCO and coordinates over 90 national centres worldwide. Each national centre assigns ISSNs to serials published within its jurisdiction and contributes records to the ISSN International Register. The Library of Congress serves as the US national ISSN centre. ISO Technical Committee 46 (Information and documentation), Subcommittee 9 (Identification and description) maintains the underlying standard ISO 3297.
Notable Implementations
The ISSN is used in virtually every library catalog and bibliographic database worldwide. It is a key identifier in MARC records, in the OpenURL framework for link resolvers, and in CrossRef's metadata for scholarly articles. Publishers use ISSNs in their systems for subscription management and rights tracking. The ISSN also appears in EAN-13 barcodes on serial covers (using the 977 prefix). National legal deposit systems frequently require ISSN assignment.
Related Standards
- MARC 21 -- Encodes ISSN in field 022 of bibliographic records, with subfields for cancelled and linking ISSNs.
- ISBN -- The analogous identifier for books (monographs), governed by a separate standard (ISO 2108).
- DOI -- Digital Object Identifiers for individual articles often incorporate the ISSN of the containing journal.