Background. Recognition that early sun exposure is an important risk factor for cutaneous melanoma in white populations has led to efforts to reduce children's sun exposure. 'Kidskin' was a non-randomized, school-based sun protection intervention trial in Perth, Western Australia (1995-1999). Its aim was to determine the extent to which such a program could reduce children's sun exposure.Methods. Kidskin involved 1614 children assigned to one of three groups: a Control, a 'Moderate' and a 'High' intervention group of 14, 11 and 8 schools respectively. The unit of assignment was the school. Control schools received the standard health education curriculum, while intervention schools received a rnulti-component intervention including a specially designed curriculum. The High intervention group received additional components. Outcomes included parent reported sun-related behaviors and objectively measured suntan at the end of summer vacation. These outcomes were observed every 2 years. Statistical analyses allowed for correlations between students within schools.Results. Kidskin initially had favorable effects on reported sun exposure and measured suntan. However, at the end of the 4-year program, and again 2 years later, little evidence of a favorable effect remained.Conclusions. The benefits of childhood sun protection interventions may not last beyond the life of the program. (c) 2005 Elsevier Inc. All rights reserved.