Samenvatting
Since 1 June 1975, the Netherlands has a mandatory seatbelt law for drivers and front passengers. In the month of April 1988 the province of Utrecht has held an action to increase the use of safety belts with 20%. Police was asked to control intensively. There were two periods. In the first one the police has a preventive policy, in the second the policy was repressive. About 100.000 cars were under surveillance. It can be stated that the action on the whole has been successful.