text: Notification The process of designating a site as of Special Scientific Interest is called notification; this is followed by consultation with the site's owners and occupiers, and the notification is then confirmed or withdrawn (in whole or part). At the time of the passing of the Wildlife and Countryside Act 1981, many SSSIs were already in existence, having been notified over the previous decades under the National Parks and Access to the Countryside Act 1949. Each of these was considered in turn, and either denotified, or renotified—brought under the provisions of the new Act, often with boundary changes. This complex process took some ten years to complete for the several thousand SSSIs.
  For the purposes of selecting the original tranche of SSSIs, Natural England's predecessors (the Nature Conservancy, the Nature Conservancy Council and English Nature) used a system termed "areas of search" (AOSs). In England these were largely based on the 1974–1996 administrative counties (with larger counties divided into two or more areas), whereas in Scotland and Wales they are based around districts. The individual AOSs are between  and  in size. There were 59 AOSs in England, 12 in Wales, and 44 in Scotland. Watsonian vice-counties were formerly used for selection over the whole of Great Britain.