In order to ensure global uniformity when describing the habitat in which a taxon occurs, the threats to a taxon, what conservation measures are in place or are needed, and whether or not the taxon is utilized, a set of standard terms (Classification Schemes; formerly referred to as Authority Files) have been developed for documenting taxa on the IUCN Red List. These Classification Schemes are still being developed and tested and not all of them have been implemented in this version of the IUCN Red List.
The Classification Schemes for Threats and Conservation Actions recently underwent a major review as part of a joint initiative between the IUCN Red List Partnership and The Conservation Measures Partnership now in use (see http://conservationmeasures.org/CMP/IUCN/Site_Page.cfm for further details about the schemes.
The three Classification Schemes used in this version of the Red List are
