Air transport will in all likelihood continue to grow, both in absolute terms and in relation to other modes. Given the high income elasticity of air passenger transport, the catching-up process in middle- and low-income countries will continue to push transport demand up substantially. The current increase in both airline and airport efficiency, triggered by deregulation in the industry, is also unlikely to cease, leading to fare reductions in at least some market segments. These fare reductions will generate future growth in air travel in terms of passenger-miles.