Controlled Vocabularies

We have seen the main components of the overall structure of the required documentation system: the descriptive system and the classification scheme.

Another level of standardization is required: the standardization of content.

Part of this standardization is already provided via the descriptive system, in the form of the information entry rules or cataloguing rules. These rules, set for each element of the descriptive system, clarify the requirements and conventions regarding the use of capital letters or punctuation, word order and the manner in which information is entered.

All these rules regarding the data's format are essential for ensuring adequate indexing of information and retrieving and reusing the information over the long term.

Another level of content standardization will facilitate the search for information: terminology standardization, through the use of controlled vocabularies.

Terminology standardization
consists of choosing the most appropriate terms to describe objects consistently and systematically.

It is carried out with the help of reference tools, authority lists and thesauri.

An authority list
(also called authority file) is a list of terms that we can use to control the terms and term variants used in the collection's documentation. For example, a museum can, in the course of data collection, refer to an authority list of materials and techniques in order to ensure consistent spelling or naming of similar objects in the documentation as a whole.

There are two types of authority lists: closed lists and open lists. The closed authority list includes a precise number of terms; no new terms can be added to this list. On the other hand, an open list contains a set of terms to which it is possible to add new ones as needed.

Whether they are open or closed, authority lists are efficient tools for terminology standardization. They are an economical way to benefit from the experience of others who have already undertaken similar work and thus avoid “reinventing the wheel”. Ultimately, authority lists promote the adoption of a common language to facilitate access to your collections.

A thesaurus
generally offers a hierarchical presentation of terminology, identifying the preferred terms to use for a concept, and specifying alternate terms, generic and specific terms, as well as non-preferred terms. Certain thesauri also have notes on the scope of the terms in order to provide cataloguers with guidance on the precise meaning and use of concepts. A thesaurus can also help with research by suggesting additional search terms as they relate to a given subject.

There are already a large number of thesauri, and new ones are created regularly. For more details and for a description of the authority lists and thesauri most commonly used for heritage collections, consult the Vocabulary section of the CHIN Guide to Museum Standards.

Authority lists and thesauri vary greatly in their design and presentation, but all of them can be used in either manual or automated systems to ensure precise and coherent cataloguing. They also make information retrieval more efficient through rigorous terminological control.

Contact information for this web page

This resource was published by the Canadian Heritage Information Network (CHIN). For comments or questions regarding this content, please contact CHIN directly. To find other online resources for museum professionals, visit the CHIN homepage or the Museology and conservation topic page on

Report a problem or mistake on this page
Please select all that apply:

Thank you for your help!

You will not receive a reply. For enquiries, contact us.

Date modified: