Many adolescents are at risk of skin cancer later in life because they spend long periods outdoors, especially during summer. This study observed and surveyed adolescents (aged 15-20 years) at the beach in summer, to determine predictors of sun protection behaviour in a high-risk situation. Adolescent attitudes toward tanning and beliefs about skin cancer formed the basis of questioning. It was found that most adolescents had inadequate levels of protection from the sun. Dark current tan levels and the reported intention to sunbake directly predicted low levels of sun protection cover. Further analyses showed indirect predictors of sun protection behaviour, including tan preferences, number of days spent on the beach over summer, and social norms. The results indicate that adolescents are not adequately modifying their behaviour to match the degree of risk to which they are exposing themselves. It appears that their behaviour is influenced by image-related factors in ways which reduce their use of optimal sun protection.