INDIVIDUAL interviews were conducted with 726 Glasgow children aged between six and 17 years. About 80 per cent of the children of primary school age favoured a ban on cigarette advertising, giving concern about health as the major reason for this. The proportion of children of secondary school age who favoured a ban decreased from 68 per cent among the 12- and 13-year-olds, to 44 percent among the 16- and 17-year-olds. Secondary school children tended to mention health concerns and the persuasive function of advertising when giving reasons for a ban. Smokers and children who said they would smoke when they were older tended to be less in favour of a ban on cigarette advertising. These findings, taken in conjunction with other research findings, suggest that cigarette advertising may have predisposing as well as reinforcing effects on children's smoking behaviour.