An interesting issue related to risk and acceptability considerations is raised by Erskine (1996). Erskine makes the distinction between risks to those who have access to cars and those who do not have access. He points out that, although risks associated with the use of cars, in terms of both the number of casualties and fatalities per vehicle- km travelled, have been decreasing considerably over the years, it is the parts of the population that do not have access to cars, i.e. the poor, the young, the old and women (i.e the nondriving population) that are adversely affected by the increased exposure to motorised travel. In order to come to more socially responsible decisions, the needs of these separate populations should be taken into account.