The 10th of March 2001 will mark the two-hundredth anniversary of the first census of population and should be an opportunity to look back not merely at the history of census-gathering but at the development of the population, economy and society of the British Isles. [We describe] a major university-based project led by ourselves and funded by the Economic and Social Research Council, the Leverhulme Trust and other bodies.... The project is supported by ONS [Office for National Statistics] and one of our central goals is to create an historical social atlas for publication at the bi-centenary.