A report is made on the strategy and tactics of an environmental medical, group-diagnostic study of children which was carried out by order of the Hessian Minister of Social Security within the framework of the Lufreinhalteplan (Clean Air Plan) Rhine/Main in the time from 1982 to 1986. This is a group-diagnostic examination of ten-year-old healthy children in the burdened area Rhine/Main (Wiesbaden, Frankfurt) and in the control areas of Freiburg and Starnberg. The objective of the study is to register the influence of the environment, in particular of air pollution, on a portion of the child population, especially with regard to persons at risk who react particularly sensitive to environmental influences and/or who have special health problems. In this connection it is attempted to convert the measuring data collected for characterizing the environment (ambient air) into effect-oriented data. The targets examined, i.e. anthropometric and clinical examinations as well as microbiological, immunologic and haematologic tests and the analysis of hair are to be evaluated in addition to family and social factors. Beyond that the attempt is made to correlate the results of the study with the biometeorological effective variables.