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DCMI Usage Board - Guidelines for Vocabulary and Encoding Scheme Qualifiers


Guidelines for Vocabulary and Encoding Scheme Qualifiers

Traugott Koch,
Date Issued:
Is Replaced By:
Latest version:
Status of Document: This is a DCMI Usage Board Working Draft.
Description of document:


1. General

  • 1.1 DCMI does not approve subject vocabulary schemes, but acknowledges formally maintained schemes as suitable for use with DC metadata. Thus, the schemes have the status "Registered" which does not imply that they are explicitely recommended by the DCMI.
  • 1.2 DCMI maintained schemes have the status "Recommended". Encoding schemes for other DCMES elements than Subject can have the status "Conforming" or "Recommended".

2. Registration process

  • 2.1 Everyone can propose a scheme for registration by submitting the required information to the web form at:
  • 2.2 The DCMI Usage Board applies a "fast track" decision process involving the rules and criteria listed below.
  • 2.3 Schemes given the status "Registered" (or "Conforming" or "Recommended") are included in the document "Dublin Core Metadata Registered Encoding Schemes" at
  • 2.4 For each scheme the list should provide the following information:
    • Name of the scheme
    • Token/acronym
    • Maintenance agency
    • Contact person
    • Email address
    • Online access (URL. if applicable)
    • Access information (URL or physical address)
    • Additional information about the scheme
    • Domain(s) and extent of usage

Ex.: Dewey Decimal Classification | DDC | OCLC Forest Press | Joan Mitchell | | Web Dewey in CORC | Dewey products | License required | Most frequently used universal classification system for library OPACs and national bibliographies; limited recent usage in web catalogues etc. |

  1. Rules
  • 3.1 Rules about what kind of schemes will be registered
    • 3.1.1 Schemes which are created and maintained by trusted authorities and properly published are registered.
  • 3.2 Rules about the naming of the schemes
    • 3.2.1 Schemes should be named with their official names. The name of the organization maintaining or owning the scheme is rarely sufficient since it does not unambiguously stand for the vocabulary alone.
    • 3.2.2 The scheme names and tokens are only appropriate for an unchanged use of an official version of the scheme. Unofficial versions, modified versions, unofficial translations and similar should not use the official label but apply a local name (e.g. based on the service, project or provider name. Ex.: The DutchESS service is using a local variant of the BC classification. It should be named DutchESSC or DutchESS-BC if it is really close to the official scheme).
    • 3.2.3 An unaltered subset of an official scheme does not need to be indicated or named differently.
  • 3.3 Rules about the tokens/acronyms used as DCMI qualifier labels
    • 3.3.1 The tokens must be unique.
    • 3.3.2 Existing official acronyms or short names should be used as tokens.
    • 3.3.3 In case communication with the scheme owner does not result in an agreed label, the Usage Board creates and lists a suitable label. In this case tokens established in other applications should be selected primarily.
    • 3.3.4 Official translated versions receive a label where a standard language code is added, e.g. DDC-fr. This is necessary since translated versions are rarely fully equivalent.
  • 3.4 Rules about the specification of scheme versions
    • 3.4.1 The DCMI encoding schemes list does register versions of the schemes if they appear to be important and/or if it is requested by a user applying for registration.
    • 3.4.2 Versioned schemes should be registered and used when there is a considerable probability that databases exist which apply terms and classes belonging to older versions of the scheme.
    • 3.4.3 The official version of the scheme used should be indicated like in the following examples: DDC21, DDC21ab-fr (abriched DDC version 21 in French), MSC2000.

Draft list of candidate vocabularies [cached copy]