Immunisations are among the most important and effective preventive measures available in the field of medicine. Modern vaccines are well tolerated and adverse drug reactions are only observed in rare cases. The immediate aim of immunisation is to protect the vaccinated person from an infectious disease. If high vaccination rates are achieved, it is possible to eliminate individual pathogens regionally and eventually eradicate them worldwide. The elimination of measles and poliomyelitis are declared and achievable goals of national and international health policy. This goal has already been achieved for poliomyelitis in Europe and other areas.