A nationwide random sample of 15,169 Norwegian high school students completed a questionnaire about tanning habits, physical self-concept, attitudes, beliefs, and values. Although 90% of the adolescents did use sunscreen, less than 25% used an adequate sun-protection factor, and only 50% applied the sunscreen an adequate number of times when sunbathing. Multiple regression analyses identified these predictors of sunbathing: opportunity to sunbathe, tender skin, heavy smoking, playing down the risk for skin cancer, valuing physical appearance, friends' use of sunscreen (girls only), a positive attitude toward having a tan, favorable physical self-concept, friends' use of sunbeds, and friends' sunbathing. Sunscreen use was also predicted by opportunity to sunbathe and skin type. Furthermore, the effects of perceived risk for skin cancer and peers' use of sunscreen were particularly strong.