On behalf of Working Group 51 of the CIB (International Council of Building Research), an international survey of research into road traffic noise has been carried out. About 500 questionnaires were distributed at the International Congress on Acoustics, London, 1974, at a satellite meeting of the Congress in Southampton, and by post. About 90 replies were received and this report presents a summary of the replies.

The questionnaire listed a wide range of research topics and this report lists the research on each topic, country by country, together with the names of those carrying the research and references to published papers. A list of the names and addresses of the research workers is given, and the questionnaire is reproduced as the Appendix to this report.