The London Air Quality Network was set up in 1993 to co-ordinate and improve air quality monitoring and provide data for informed action to reduce air pollution in London. For the first time London local authorities and health agencies have worked together to pool expertise and provide the basis for meeting the challenge of a sustainable future, set out at the United Nations Conference on Environment and Development (the "Earth Summit") at Rio in 1992. The first annual report of the London Air Quality Network was published in Febuary 1994 and covered data and policy to 1993.

Public concern about London's air quality is increasing. Parts of London now experience poor air quality whenever the weather is settled, with levels of pollution exceeding international health guidelines. Levels of respiratory disease, especially asthma, continue to rise although there is no clear evidence of air pollution causing such diseases. It is however widely accepted that pollutants worsen the symptons of existing sufferers.

There is a growing consensus that air pollution in London is predominantly linked with traffic and that levels of pollution must be reduced through changes in transport policy. This is reflected in major reports published in 1994, including those by the Royal Commission on Environmental Pollution on transport and the environment and the report from the House of Commons Select Comittee on transport related pollution in London, which incorporates evidence from the London Boroughs Association, Association of London Authorities and the South East Institute of Public Health.

One conclusion from the first annual report of the London Air Quality Network was that the weather conditions during 1993 were not of the type to cause pollution episodes and that the generally good air quality in that year should not be a reason for complacency. This report confirms that the concern was justified as summer photochemistry and winter foggy conditions caused poor air quality to be experienced regularly throughout 1994.