Carstairs scores, first calculated in the 1980s based on data from the 1981 Census, were designed as a summary measure of relative deprivation within small populations. They were based on four indicators from the census which were considered to represent material disadvantage, and have since been widely used to examine the relationship between deprivation and health. This article describes how Carstairs scores were calculated for England and Wales based on data from the 2001 Census and also presents the resulting geographical patterns of deprivation.