• England and Wales;
  • census;
  • dissimilarity;
  • segregation;
  • index;
  • scale

The paper considers the scale – the measure, extent, and dimension – of uneven distributions in space for a wide range of census variables. While the traditional ‘index of dissimilarity’ is affected by random as well as social factors, a solution presented here allows the index to be calculated even for very small populations. Small areas across England and Wales tend to be fairly similar demographically but quite diverse on ethnic and socio-economic measures. Differences between areas become more noticeable as we move from districts, to wards, to enumeration districts, but the rate of differentiation depends heavily on the variables considered.