Compulsive buying is an understudied, but growing, dysfunctional consumer behaviour with harmful psychological and financial consequences. Clinical perspectives treat it as a psychiatric disorder, whereas recent proposals emphasize the increasing endorsement of materialistic values as a cause of uncontrolled buying (e.g. Dittmar, 2004b; Kasser & Kanner, 2004). The present research aims to improve understanding of compulsive buying through examining gender, age, and endorsement of materialistic values as key predictors in three UK questionnaire studies, which sampled individuals who had contacted a self-help organization and residentially matched 'controls' (N = 330), consumer panelists from a multinational corporation (N = 250), and 16- to 18-year-old adolescents (N = 195). The results confirmed previously documented gender differences, and showed that younger people are more prone to compulsive buying. The central findings were that materialistic value endorsement emerged as the strongest predictor of individuals' compulsive buying, and that it significantly mediated the observed age differences.