An unclouded look at territorial autonomy back and forward, 100 years after the establishment of the first "modern" territorial autonomy in a democratic state: the Åland Islands in Finland in 1921/22. Where has autonomy been successful to ensure minority protection and self-government, where has it failed, where is it in crisis, where is it aspired to? In which cases would autonomy settle open conflicts between states and regional communities, and in which cases of national emancipation is autonomy no longer sufficient? In 2021, after 100 years of experience with territorial autonomy in all parts of the world, this concept for solving sub-state conflicts is still underestimated. Background information and assessments on the development to date and on the perspectives for the application of territorial autonomy in various regions worldwide by the author of "The World's Modern Autonomy Systems", conversations with ten outstanding personalities from politics and science in these regions and a foreword by the South Tyrolean politician and scientist Oskar Peterlini, former senator in Rome.