The symposium held at Freiburg on September 10th, 1983 had been con­ cerned with methodical problems in early detection. chiefly of can­ cer. The first lectures dealt with mathematical models. They were followed by contributions to the possibilities of obtaining the pa­ rameters required by the models and for the assessment of the me­ thods. The two final lectures outlined a monitoring system for rare diseases and some problems in early detecting heart and circulation diseases. The meeting had been organized by the Deutsche Gesellschaft fUr Me­ dizinische Dokumentation. Informatik und Statistik (GMDS). Thus the programme committee was set up by the heads of the GMDS