The reported study compared the efficacy of three self-affirmation manipulations in reducing defensive processing and instigating behaviour change in response to personally relevant information about the health risks of sunbathing. White female sunbathers (N = 162) were recruited on a beach in the south of England. Participants were randomly allocated to a 'values affirmation' condition, a 'kindness affirmation' condition, a 'positive traits affirmation' condition, or a no affirmation 'control' condition. In the 'positive traits affirmation' condition the self-affirmation task was incorporated into a leaflet presenting the health risk information. Findings supported the hypothesis that participants in the three self-affirmation conditions would engage in less-defensive processing of the health-risk information than those in the 'control' condition. For the behavioural measure, however, only those participants in the 'positive traits affirmation' condition were more likely to request a free sample of sunscreen than those in the control condition. The implications of these findings for self-affirmation theory and the development of effective health promotion campaigns are discussed.