Abstract
Modern economies rely on just in time logistics. On time business travel is just as critical. However, as traffic grows, reliability tends to suffer. In the UK, it is estimated that 30% to 50% of freight journeys are now delayed by congestion. Advanced ITS can improve journey reliability by 30%. This aspect appears to be highly valued by road users, but has been disregarded in conventional cost-benefit analysis, which has only counted savings in average journey times, travel costs and accidents. This paper describes how there are now ways of measuring reliability gains, but further work is needed to assess its true value.