Hermann Nitsch is one of the founding fathers of Viennese Actionism and one of the most important contemporary action artists. His magnum opus, the Orgien Mysterien Theater, is a new form of Gesamtkunstwerk. The idea for it emerged in 1957 and has led, to date, to the realisation of 142 actions, 70 painting actions and countless works in various art disciplines. After numerous publications and editions by Nitsch and comprehensive literature on his Orgien Mysterien Theater, the editor has compiled and elucidated all the documentation, with more than 1,500 illustrations, photos, drawings and scores, with the help of Nitsch and his meticulously kept archive. The various registers open up the monumental work.