In Sweden a majority of child fatalities (under 15 years) are due to injuries, and of these about 40% are the result of traffic accidents - about the same rate as in the USA. Children are exposed to high risks in traffic, but despite increased traffic volume it has still been possible to decrease numbers of injuries and deaths. However, the various preventive interventions made have not been fully evaluated. The main objective of this article is to study long-term effects of legislation and local promotion of child-restraint use in motor vehicles. Subgoals are to describe the level of restraint use for children in cars and to study changes in mortality and morbidity patterns in regard to differences among age groups and geographical areas (morbidity).