Sudden cardiac arrest is a serious public health problem in Hong Kong, with up to 85% of victims not surviving to hospital admission. International research findings show that teaching cardiopulmonary resuscitation (CPR) to lay bystanders can significantly improve out-of-hospital survival rates. A particular target group for CPR training and education is high school students. Since the commonest site of sudden cardiac deaths in Hong Kong occur at home, school-age adolescents are likely to be the only available bystanders in many emergent situations.