Werner Catel (27 June 1894 – 30 April 1981), Professor of Neurology and Psychiatry at the University of Leipzig, was one of three doctors considered an expert on the programme of euthanasia for children and participated in the Action T4 "euthanasia" program for the Nazis, the other two being Hans Heinze and Ernst Wentzler.In early 1939 a farm labourer called Richard Kretschmar requested Catel's permission to euthanize one of his children, now identified as Gerhard Kretschmar, who had been born blind and deformed.