For policing purposes the country is divided into 6 regions, each of which is commanded by an Assistant Commissioner. The 6 regions are:Dublin Metropolitan RegionNorthern RegionWestern RegionEastern RegionSouthern RegionSouth Eastern RegionThe duties of the regional Assistant Commissioners are mainly operational. They are responsible for:Ensuring the operational efficiency of their respective region;The quality of operational management exercised by their Divisional and District Officers.Each region is divided into divisions commanded by a Chief Superintendent, and each division is then divided into districts commanded by a Superintendent. A Superintendent in charge of a district is also known as the District Officer. He/she is assisted by a number of Inspectors. The districts are divided into sub-districts, each normally the responsibility of a Sergeant. Each sub-district usually has only 1 station, the strength of which may vary from 3 to 100 Gardaí. In some areas there are stations known as sub-stations which for administrative purposes are attached to a parent station. These sub-stations are usually occupied by 1 garda member. There are 564 Garda Stations throughout the country.