Investments in more diversiWed local economic development of regions may be one way of reducing the growing demands of air traYc. This issue was raised in suggestions by interviewees about the need for alternative conceptions of the economy. Where mobility needs must be met, modal change, especially to high-speed rail, is regarded as a sensible option for short-range traYc, for both economic and environmental reasons (Royal Commission on Environmental Pollution, 2002, p. 33–34).