Acknowledging that different people may respond differently to different products and services and to the way information is presented to them, is a core principle in marketing. In fact, commercial marketers spend a great deal of resources identifying and determining which segments will be most profitable for them. Not surprisingly, then, market segmentation and target marketing have been emphasised from the start in the early literature defining or describing social marketing and its application to public health campaigns (e.g., Lancaster, McIlwain and Lancaster 1983; Manoff 1985; Novelli 1984). In today’s social marketing literature, the need to target programmes at different segments of the population is taken for granted.