This paper examines relations between eugenics and genetics during the Weimar Republic. Research aims and requests for funding were motivated by a sense that biology could contribute to national reconstruction after the First World War. Geneticists' participation in social policy-making is assessed, as well as the rise of interest in eugenics and racial biology among public health officials. It was important that eugenics be acceptable to the Centre Party, and a sometime Jesuit, Hermann Muckermann, took a leading role as intermediary (...) between the state and human geneticists in the founding of the Institute for Anthropology, Human Heredity and Eugenics. Earlier plans to establish a national institute, the organization of the Institute as it actually materialized, and the scope of research are considered. Finally, the dislocation in 1933 is assessed in order to further emphasize how the Institute was deeply embedded in the Weimar social structure. (shrink)