To understand the difference between areas, policy makers need to focus on the important characteristics of areas, be they geographical or socio-economic. One way of doing this is to group areas together according to characteristics they share. These groupings are called classifications. The purpose of this article is to examine two of these classifications, the 2004 Rural and Urban Definition of England and Wales and the suite of area classifications based on the 2001 Census of Population. The article introduces these, contrasts the information they highlight and examines how combining the classifications can provide more than using either separately.