The ethical credentials of advertising in regard to young people have been questioned for some time. It is thus intriguing that the same scrutiny has never been directed at the concomitant practice of segmentation. Market segments are usually assumed to exist quite independently of the targeting process and are thus not considered within the same agenda as advertising. But what if advertisers influence the formation of segments? In this postulate, firms are not creating a product for a segment but instead are creating a segment for a product. Advertising and segmentation become interlinked and the ethical concerns expressed over advertising must also be applied to segmentation. The article highlights the link between advertising and segmentation and presents empirical evidence that adolescent attitude/value-based segments can be influenced by advertising. If this result can be generalized, the ethical debate on advertising needs to be widened to include the commercial practice of segmentation.