Geodemographic classifications group small area geography into categories based on shared population and built environment characteristics. This process of “codification” aims to create a common language for the description of salient internal structure of places, and by extension, enable their comparison across geographic contexts. The typological study of areas is not a new phenomenon, and contemporary geodemographics emerged from research conducted in the 1970s that aimed at providing a new method of targeting deprivation relief funding within the city of Liverpool. This city level model was later extended for the national context, and became the antecedent of contemporary geodemographic classification. This paper explores the origins of geodemographics, to first illustrate that the coding of areas is not just a contemporary practice; and then extends this discussion to consider how methodological choices influence classification structure. Being open with such methods is argued as being essential for classifications to engender greater social responsibility.