Adolf Hitler did not personally attend the Wannsee Conference. The conference was organized and led by Reinhard Heydrich, the chief of the Nazi security service (Sicherheitsdienst or SD) and one of the main architects of the Holocaust. Hitler's role in the decision-making process leading to the Holocaust, including the extermination of European Jews, was more general and indirect. It involved giving broad authorization and creating an atmosphere that encouraged Nazi officials to take radical and genocidal measures to achieve their ideological goals.