Commissioned by the Dutch Ministry of Transport, Public Works and Water Management, SWOV made an inventory of preventive alcolock implementation and stimulation worldwide. Preventive alcolock installation is not related to judicial or administrative offender programmes. In order to obtain the desired information, SWOV sent a questionnaire to the most important actors regarding preventive alcolock implementation in Europe, North America and Australia. Based on the results, recommendations are made for the situation in the Netherlands, focusing on two clearly distinguished driver categories: professional drivers and drivers with an alcohol problem. The inventory of international experiences did not yield any (scientific) evidence of the safety effects of preventive use of alcolocks. As preventive use has not internationally been adopted much, there are few leads for a successful introduction in the Netherlands. However, international experiences are a basis for a number of considerations in relation with this topic. Mandatory alcolock installation in vehicles that are used for the transport of school children and disabled people might be considered because of the vulnerability and dependence of these groups. In order to gain sufficient public support, prior implementation of an alcolock programme for drink-driving offenders is recommendable. It could be considered to first discuss the issue with the transport sector concerned, provide information about the possibilities and/or carry out a joint demonstration project. For further use of the alcolock in a commercial environment — in trucks, taxis and public transport — further implementation of the alcolock is probably best left to free-market processes, especially if their future price gets lower, if the government lowers the legal BAC limit for professional drivers, if the government installs alcolocks in its own vehicles, and — last but not least — if the use of alcolock systems becomes less incriminating. The government can then limit itself to public information and possibly co-funding of the odd demonstration project. Concerning legislation, setting quality standards for the alcolock seems advisable, independent of whether or not their use is made mandatory. It suffices to make the existing NEN standard for preventively used alcolocks mandatory in the Netherlands. The situation is more complex for (voluntary) preventive use of alcolocks by drivers with an alcohol problem. On the one hand, an alcolock programme may have a positive road safety effect for this group, but, on the other hand, there has hardly been any experience worldwide. It therefore seems sensible to first carry out a thorough experiment. The government may have to legislate the preventive use of alcolocks by drivers with an alcohol problem. It is worthy of consideration to ask for support from the sector of care and treatment of drug addiction. This will result in relatively high costs, of which it is uncertain whether the target group can or will be prepared to settle the bill. It can of course be investigated whether alternative sources of financing can be found.