In the Third Reich hereditarian approaches and their eugenic implications seemed to offer possibilities for fundamental progress in the fight against cancer. This did not lead to an exclusive emphasis on genetics in theory or practice. The concept of a hereditary predisposition for cancer, the Krebsdisposition or Krebsbereitschaft, led to flexible multifactor approaches, including proposals for both eugenic and social-hygienic measures. These approaches were not typical of German medicine alone. In the Netherlands hereditarian approaches did not play a central role in the 1930s. They lacked institutional support in a country where health policies were characterised by indirect strategies working through intermediaries such as general practitioners and home nursing organisations. However, potentially the elements for similar anti-cancer policies as in Germany were present. The German occupation offered opportunities to develop these elements (concepts, institutions, personnel). This development was blocked because of the political radicalisation during the war and the German defeat.