The carriers of the German Statutory Health Care System have recognized that only mammographic screening according to the European Guidelines for the Quality Assurance of Mammography Screening will permit early detection of breast cancer with an acceptable risk/benefit ratio. In the German pilot projects, regional mammography screening programmes according to the European guidelines are being tested in the framework of the German health care system. The European guidelines require comprehensive quality assurance of all relevant steps in the chain of events involved in screening, from invitation on to therapy and follow-up. Such comprehensive quality assurance involves several medical specialities and other professional groups dealing with out-patient and in-patient health care and requires long-term cooperation with public institutions (population registries, cancer registries). The objective of the pilot projects is to test the organizational and legal conditions essential to introduction of a mammographic screening programme according to the European quality assurance guidelines in Germany.