OAI-PMH

OAI-PMH

Open Archives Initiative Protocol for Metadata Harvesting: a low-barrier HTTP/XML protocol that allows a 'data provider' system (typically a repository or CRIS) to expose its metadata records for incremental harvesting by 'service providers' (aggregators, search services, national portals).

ByCASRAI Editorial Board

· Last updated 21 May 2026

OAI-PMH (current version 2.0, 2002) defines six verbs (Identify, ListMetadataFormats, ListSets, ListIdentifiers, ListRecords, GetRecord) over HTTP GET, with responses in XML. The protocol is metadata-format-agnostic: Dublin Core is mandatory, but CERIF-XML, MODS, RIOXX, JATS, and many others can be exposed in parallel. Despite being twenty years old, OAI-PMH remains the dominant repository-harvesting protocol in research-information ecosystems, including OpenAIRE harvest, BASE, CORE, and national aggregators.

References

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Use in your systems

JATS XML <role> element

xml

<role vocab="credit"
      vocab-identifier="https://casrai.org/dictionary/"
      vocab-term="OAI-PMH"
      vocab-term-identifier="https://casrai.org/dictionary/term/oai-pmh" />

Schema.org DefinedTerm (JSON-LD)

json

{
  "@context": "https://schema.org",
  "@type": "DefinedTerm",
  "name": "OAI-PMH",
  "identifier": "https://casrai.org/dictionary/term/oai-pmh",
  "description": "Open Archives Initiative Protocol for Metadata Harvesting: a low-barrier HTTP/XML protocol that allows a 'data provider' system (typically a repository or CRIS) to expose its metadata records for incremental harvesting by 'service providers' (aggregators, search services, national portals).",
  "inDefinedTermSet": "https://casrai.org/dictionary/domain/research-information-systems-and-integration/",
  "url": "https://casrai.org/dictionary/term/oai-pmh",
  "sameAs": [
    "Open Archives Initiative Protocol for Metadata Harvesting"
  ],
  "license": "https://creativecommons.org/licenses/by/4.0/"
}

Worked examples

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References

Use in your systems