Under the so-called “child euthanasia” program, the National Socialist regime created a network of institutions for the elimination of children deemed “unworthy of life”. In July 1940, on the premises of one of Europe’s largest psychiatric hospitals, one of the first of these facilities was installed under the name “Spiegelgrund”. During the following years, hundreds of children and adolescents were examined, observed, and often killed. Their brains and other organs were preserved for scientific use until long after the war, leading to a belated reckoning with Austria’s Nazi past in the early 2000s. The paper traces the history of the Spiegelgrund from its historical roots to the post-war, including its role within Vienna’s social welfare system during the years 1940 to 1945.