With the multiplying numbers of vehicles on European roads, sustainability in road transportation has become the keyword. Participants at the recent annual conference of the Royal Geographical Society in Glasgow, UK, have gone so far as to propose a ban on private cars, suggesting that cars be phased out over a period of 30 years. The British government's response has been typically vague. Says environment secretary John Gummer: "The fundamental problem with the transport issue is that there is no single solution. There are those who long for the