Examples
Worked examples
- Is an instance
A book record in MODS with titleInfo, names with roles (creator, editor, illustrator), publisher, language, subjects, and ISBN identifier.
- Is an instance
MODS metadata embedded in the dmdSec of a METS object.
Editorial commentary
MODS is maintained by the Library of Congress’s Network Development and MARC Standards Office as an XML schema for descriptive bibliographic metadata. It sits deliberately between two poles: Dublin Core’s roughly fifteen flat, unqualified elements are too coarse for many library and archival description needs, while full MARCXML carries decades of cataloguing-rule complexity that most repository platforms don’t need to reproduce. MODS keeps most of MARC’s descriptive expressiveness — structured names with roles, hierarchical part/series relationships, controlled subject and classification schemes, typed identifiers — in a schema considerably easier to read, generate, and validate than MARC.
Where it fits in a repository stack
MODS commonly appears in two roles in digital-library and RDM infrastructure: as a repository’s primary descriptive metadata format (DSpace and Fedora-based repositories both support MODS, either natively or as a mapping target alongside Dublin Core), and embedded within the descriptive-metadata section (dmdSec) of a METS package for complex digital objects — multi-page items, compound objects, or born-digital collections that need structural metadata (METS) and rich descriptive metadata (MODS) together. When an institution is choosing a schema for a digital-object repository and Dublin Core’s flat element set is judged too thin, MODS is one of the standard next steps up, alongside schema-specific alternatives like the DataCite Metadata Schema for datasets specifically — see the CASRAI guide How to Choose a Metadata Schema for a Dataset.
Scope note: MODS’s full element-by-element cataloguing rules are library-cataloguing territory owned by the Library of Congress’s own documentation (loc.gov/standards/mods); this entry orients a repository or CRIS manager to what MODS is for and when it’s the right choice, not how to catalogue in it.
References
- Library of Congress, ‘MODS: Metadata Object Description Schema’ (loc.gov/standards/mods).
Also known as
Metadata Object Description Schema
Machine-readable encodings
Use in your systems
<role vocab="credit"
vocab-identifier="https://casrai.org/dictionary/"
vocab-term="MODS"
vocab-term-identifier="https://casrai.org/dictionary/term/mods" />{
"@context": "https://schema.org",
"@type": "DefinedTerm",
"@id": "https://casrai.org/dictionary/term/mods",
"name": "MODS",
"identifier": "https://casrai.org/dictionary/term/mods",
"description": "Metadata Object Description Schema: a Library of Congress XML schema for descriptive bibliographic metadata, designed as a richer alternative to Dublin Core and a more flexible alternative to MARC for library, archive, and repository contexts.",
"inDefinedTermSet": "https://casrai.org/dictionary/domain/research-info-systems#set",
"url": "https://casrai.org/dictionary/term/mods",
"sameAs": [
"Metadata Object Description Schema"
],
"license": "https://creativecommons.org/licenses/by/4.0/",
"publisher": {
"@id": "https://casrai.org/#organization"
},
"author": {
"@id": "https://casrai.org/#editorial-team"
},
"datePublished": "2026-05-21T02:16:54",
"dateModified": "2026-08-22T16:17:02",
"inLanguage": "en-GB",
"isAccessibleForFree": true
}
