1600 schoolchildren aged 13 to 18 answered an anonimus, self administered questionnaire, in a cross sectional study to estimate the prevalence of cigarette smoking in the high grades schools in Andorra. 46.6% answered they did smoke cigarettes, either daily (11.2%) or occasionally (35.4%). Ten per cent of actual smokers did already smoke at age 10, and 50% at age 13. More girls (48.8%) than boys (44.4%) smoked (p less than 0.05) but boys smoked a greater number of cigarettes (p less than 0.001). Ninety five percent smoked Virginia tobacco, and little more than 50% used filter tipped cigarettes. Two thirds of smokers inhaled the smoke of cigarettes; this was more common among daily smokers. Again two thirds of smokers answered they would be prepared to quit smoking. 31% of those who had tried smoking said they believed they would smoke in the future, while only 5.6% of those that never smoked previously said so (p less than 0.001). Actual smokers answered they believed that they would not smoke in the future much less often than non smokers. Parents let boys smoke more than girls when the children started doing so, particularly before age thirteen and after age fifteen. These are the first available data about the community studied describing some features of its cigarette smoking habit. Their knowledge may well help to plan disease protection and health promotion developments addressed to youngsters in Andorra.