Today's environmental information systems combine the latest sensor and monitor technologies with data transfer; data base developments, quality assurance, statistical and numerical models and advanced computer platforms for processing, distribution and presenting data and model results. Geographical Information Systems (GIS) are an important tool, particular for the presentation of data. An important part of the integrated air quality management system is the establishment of a monitoring programme for air quality. Once the objective of the air monitoring programme is well defined, a certain operational sequence has to be followed. The best possible definition of the air pollution problem, together with the analysis of the personnel, budget and equipment available, represent the basis for the final design. The specification of monitoring objectives, data quality objectives together with proper site selection, data quality assurance and well-defined data presentation and assessment are important elements in this process.