Maintenance of property values is one of our common concerns. An unwelcome local development might knock thousands off the value and be fiercely resisted in the planning stages. Noise is often one of the most prominent factors in the objectors' armoury, so that it is clearly relevant to have a quantification of the effects of noise on property values. The main noises which affect property values follow from developments in transportation. Other, more localised, noisy developments may also occur, such as entertainment and industrial complexes, but these are not yet assessed as devaluers. However, air, road and rail have been studied in some detail, particularly air and road transport.