The Office for National Statistics (ONS) is responsible for running the decennial Census of Population. Since 1801, every 10 years (with the exception of 1941) the nation has set aside one day for the Census - a count of all people and households. It is the most complete source of information about the population that we have. The latest Census was held on Sunday 29 April 2001.
Every effort is made to include everyone, and that is why the Census is so important. It is the only survey which provides a detailed picture of the entire population, and is unique because it covers everyone at the same time and asks the same core questions everywhere, making it easy to compare different parts of the country.
The information that the Census provides allows central and local Government, health authorities and many other public and private sector organisations to target their resources and manage their business more effectively, and to plan housing, education, health and transport services for the subsequent decade.
In England and Wales, the Census is planned and carried out by the Office for National Statistics in consultation with the Welsh Assembly Government. Elsewhere in the UK, responsibility lies with the General Register Office for Scotland and the Northern Ireland Statistics and Research Agency.
Planning for the next Census in 2011 is well underway.