A scoping study report (Davis et al, 2003) reviewed existing knowledge about impaired driving – with special reference to developing countries. It was carried out by a team led by the TRL, including three experts from developing countries who conducted a series of regional reviews that covered a large proportion of developing countries around the world. It was anticipated that this approach would provide more valuable in-depth (and sometimes unpublished) information about a significant number of countries. The atached is a summary report made by GRSP.