John Adams is a reader in geography at University College London. He was a member of the original board of directors of Friends of the Earth in the early 1970s and has been involved in the debate about transport and its social and environmental consequences ever since. His 1981 book Transport Planning: Vision and Practice explored the influence of competing 'visions of progress'. This is a theme to which he has returned in his most recent book Risk (UCL Press, 1995) described by The Economist as 'a beguiling book' and by Nature as 'extremely counterintuitive... stimulating and rewarding'. He observes that the arguments deployed in the transport debate - and other environmental debates such as that about nuclear power - have changed extraordinarily little in the last 25 years. Despite the accumulation of 25 years worth of scientific evidence, agreement seems no closer. The believers in economic growth and development and the defenders of the environment are still arguing from different premises.