Britain and Northern Ireland are divided into BTO Regions, in each of which is a dedicated Atlas Regional Organiser whose job it is to co-ordinate atlas survey work between volunteers and BTO HQ. These regions consist of groups of 10km squares and are loosely based on county boundaries. To find out who your Atlas Regional Organiser is in Britain and Ireland please look at the map below (left) or use the RO finder below (right) by typing in your postcode (UK only). In the Republic of Ireland the Atlas regions are based on county boundaries and areorganised by the Irish Atlas Coordinator or individual county organisers.