The Norwegian Red List of Species 2015 has been compiled by the Norwegian Biodiversity Information Centre in cooperation with 24 committees of experts with a total of 90 members. The Norwegian Red List of Species includes species that are assessed as being at risk of
extinction within Norway. Each species is placed in one of a number of categories, which are ranked according to the level of risk that species will die out if conditions remain unchanged.
Red list assessments are only made for species that are or have been established as reproducing species in Norway. Alien species, in other words species that have been spread to Norway since 1800 by human activity, are not assessed.
Species are assessed against a set of criteria developed by the International Union for Conservation of Nature (IUCN). The criteria and guidelines for using them ensure that assessments are standardised, verifiable and objective.
The categories reflect the level of risk that a species will die out if conditions remain unchanged. Species in the categories Critically Endangered (CR), Endangered (EN) and Vulnerable (VU) are described as threatened species.
The assessments for most species groups apply to mainland Norway and adjacent Norwegian sea areas. In all, 21 402 species and 278 subspecies of vascular plants have been assessed for the 2015 edition of the Red List.