Samenvatting
This paper presents the first assessment of the effect upon traffic patterns of the Variable Message Signs (VMS) used in the SIRIUS project. Brief details of the SIRIUS project are provided. Surveys have been made prior to implementing SIRIUS, and at six monthly intervals afterwards of motorists in the Paris Region. Nearly 10,000 motorists took part. These survey results were augmented by 100 in depth interviews in a follow up survey. The aim of this latter survey was to ascertain how drivers interpreted the messages and the effect this had upon their diversion choice. The results are presented and discussed briefly. They show that driver information provided by VMS does influence traffic behaviour.