Work on this report started in September 2001 as a continuation of the work carried out between the years 1998 and 2001, which concluded with the report entitled CROSS SECTION GEOMETRY IN UNIDIRECTIONAL ROAD TUNNELS, published by PIARC in March 2001. This report shares the terminology and general approach of the previous document but adapts and extends it to cover tunnels with a single gallery and two directions of travel. The drafting of this report has involved examination of appropriate national standards and recommendations, as well as various documents of the PIARC and other international organisations that have recently come into being in response to the tragic accidents that have occurred in tunnels since 1999. The conclusions and recommendations of the report are based on common practice in various countries, as well as on the opinions of the experts on the PIARC Committee.