After touching on his own experiences, Barrie Kosky points out that operetta lost the continuity of its tradition in World War II. He calls for a radical investigation into operetta performance practice. He describes operetta as a Jewish art form not only because most of the composers, librettists and performers were Jewish but also because operetta itself is about assimilation, irony and disconnectedness. This tradition was interrupted because many Jewish artists went into exile or died in the war. After the war, everything subversive, erotic, ironic and contemporary became harmless, nostalgic, and arianized. But over the last ten years, new understanding has grown, and a new young audience is discovering operetta. Kosky maintains an operetta needs a fabulous score and must work on different levels as a combination of ‘serious but ironic’. Operetta needs characters, scenes and situations that can reveal performers’ virtuosity in mixing singing, dancing, speaking and acting. Kosky sees subversiveness and campy queerness as inherent in operetta. It appears in Offenbach’s political awareness as well as in the new definition of gender in the Weimar operetta. Kosky says new operetta requires composers and librettists familiar with the tradition but who should avoid copying operetta of the past.