In Second World War 8.4 million foreign civilian workers were used for labour in theGerman Reich, many of them were forced labourers. Civilian workers from Polandand the Soviet Union, who became mentally or physically ill and could not be cured inshort time, were sent back to their home countries. In May 1943 the transports ofmentally ill forced labourers to their home countries were stopped, as the NationalSocialist „euthanasia“ bureaucracy intervened and brought the labourers from “mentalinstitutions” to special facilities where they were killed. In 1943 and 1944 severaltransports with mentally ill forced labourers from mental institutions in the area ofBavaria and Austria are documented. In most of these cases the destinations of thetransports are unknown. The working hypothesis of this article is that the transportswent to Hartheim castle, which served as “killing centre” from 1940 to 1944. Physicallyill civilian workers were detained in camps, where many of them died because of lackof food and medical care and because of the bad hygienic situation.