The aim of this cross-sectional study was to determine the habits, practices, attitudes and knowledge about cigarette smoking among high school boys aged 15-19 years in the United Arab Emirates, and to provide a basis for comparisons with international data. The World Health Organisation questionnaire was used, together with a multi-stage stratified cluster sampling technique; 1,700 subjects aged 15 years and above were randomly selected. A total of 1,486 individuals (87.4%) from among the populations of Al-Ain City, Abu-Dhabi and Dubai Emirates participated in the study. The prevalence of smoking among the studied group was 19%; 28.2% admitted that they had smoked before but had now given up, and the remaining 52.9% denied having ever smoked. Among 18-year-olds (or older) 30.3% smoked. In 70.8% of cases a friend was reported as having been the first source of their cigarette. Fifty-four percent of smokers started between the age of 10 and 15 years. The families of 15.7% of those studied approved of their smoking, while 78.3% did not: 6% did not have an opinion. Nearly two-thirds of the smokers (66.5%) wanted to stop smoking, while the remaining third (33.5%) did not. Differences in parental education (specifically that of the father) were found to have a significant effect on attitudes towards smoking. Contrary to expectations, the highest prevalence of smoking was found among sons of university graduates, and the lowest among sons of illiterate fathers (12.6% and 24.3%, respectively). There was a statistically significant difference in respect to family income and smoking. Among the ex-smokers, religion (40%) and health (26%) were important reasons for giving up smoking. Of the smokers, 33% claimed that stress is the most important factor which makes people smoke. The source of the student's information regarding smoking hazards ww lowest from doctors (17-19%), and highest from the media (35%). All student groups were equally aware that smoking is a risk factor for lung cancer, respiratory diseases, and ischaemic heart diseases, but among the smokers only 28.3 % were very concerned about the harmful effects of cigarettes. At the time of their graduation (18 years or older), one-third of the students were already regular smokers, a figure liable to increase as they start university or work.