There are a number of different habitat classification systems that may be appropriate for use in a Preliminary Ecological Assessment. SNH is adopting the EUNIS habitat classification for terrestrial habitat data and mapping. It also correlates EUNIS habitats with habitat types listed in Annex I of the Habitats Directive. Correspondence tables support translation between EUNIS and the national habitat classifications and lists, including the NVC, UK BAP Priority Habitat types55, Phase 1 categories and habitat features on Sites of Special Scientific Interest (SSSIs).