Every market looks, from a distance, like a single undifferentiated mass of customers. It never is.

This book goes deep into the mechanics of finding the real divisions inside that mass: the variables and bases available for segmenting consumer and business markets, the analytical methods — cluster analysis, preference-based segmentation, response-based segmentation — that turn raw data into a defensible set of groups, and how to evaluate which segments are actually worth targeting.

It closes with a question too often treated as an afterthought: the ethical and privacy considerations that segmentation, done with enough data, inevitably raises.