Geodemographics may be described as the applied statistical study of the geographic distribution of population characteristics. The topic of this paper relates specifically to the application of geodemographics classification systems, to marketing questions in general, and to media analysis in particular. By way of further clarification, geodemographics classifications are neighbourhood classifications based on statistics relating to the population characteristics of each residential neighbourhood, derived from comprehensive published and publicly available sources such as census statistics. This paper considers the early development of geodemographics and neighbourhood classifications in Great Britain, where most of the pioneering work took place in respect of marketing applications of such systems. The media and marketing applications of geodemographics that have been developed will be discussed, as well as more recent developments in what has now emerged as a geodemographics industry in Great Britain. The status of the parallel developments of similar systems in a number of European countries will be outlined, as well developments in North America.