The IUCN Red List Categories and Criteria were developed for classifying species at high risk of global extinction, i.e. for assessment at the global level. At regional, national and local levels there are essentially two options: (1) to publish an unaltered subset of the global IUCN Red List encompassing those species that reproduce in the region or at any stage regularly visit the region; or (2) to assess species’ extinction risk and publish Red Lists within the specific region. For the purposes of regional conservation assessments there are important reasons to assess species’ extinction risk and publish Red Lists within specific geographically defined areas. The Guidelines for Application of IUCN Red List Criteria at regional and national levels. Version 4.0 are recommended to anyone wanting to undertake Red List assessments at the regional level.