BACKGROUND There are no recent data on smoking habits of high-school students in Greece. The primary objective of the study was to determine these epidemiological factors. METHODS The smoking habits of 927 high-school students (471 boys and 456 girls), aged between 15-18 years, in four regions of a Greek area (the island of Cos), were examined. Study data were collected using a questionnaire. RESULTS It was found that 32.48% of boys and 27.19% of girls are smokers; 43.3% had started smoking before the age of 14. The mean age for starting smoking was 14.4 +/- 1.9 years for the boys and 14.9 +/- 1.6 years for the girls. As many as 22.8% of the students smoke 6 to 10 cigarettes per day and 21.5% 16 to 20 cigarettes per day; 40.2% reported that they smoke out of spite. Students reported that their parents are aware that their offspring smoke in a proportion of 36.7%. Social standards and parental example were found to be the main determinants for starting smoking. The majority of the students (95.2%) stated that they are aware of the hazards associated with smoking. CONCLUSIONS Our findings highlight the need for smoking control interventions aimed at young people. Smoking is a major, yet preventable cause of morbidity and mortality. For these reasons, we view that adolescents should be targeted with a well-planned integrated anti-smoking policy and not just an initiative for raising awareness of smoking hazards.