Results from a survey of 10,579 schoolchildren aged 11-16 years indicated various relationships between age, smoking behaviour, health locus of control beliefs, expressed concern with different consequences of illness and beliefs in the efficacy of different strategies for staying healthy. In particular, smokers, compared with non-smokers, showed less belief in the importance of 'powerful others' or 'personal control' but more belief in the importance of 'chance' as an influence on health outcomes. With regard to consequences of illness, smokers cared more than non-smokers about not being allowed to see friends, but less about getting behind in school or being a nuisance to others; they were also less convinced of the benefits of preventive health behaviours such as eating good food and taking exercise. Implications for health education approaches are discussed.