In 1955, during a visit to Bertolt Brecht's home in East Berlin, Lotte Lenya was invited by her host to sing to him. They hadn't seen each other for a number of years, and Lenya at first demurred, feeling apprehensive about her grasp of the playwright's celebrated theories. Brecht, however, was quick to supply words of encouragement. Of all Brecht's tracts, none more warrants such circumspection than the best-known of all: the Anmerkungen zur Oper Aufstieg und Fall der Stadt Mahagonny. The first and most obvious ground for questioning the adequacy of Brecht's Anmerkungen could be seen to rest in the fact that they were formulated only after the first performance of the Mahagonny opera, which took place in Leipzig on 9 March 1930. Post festum theory is not in itself a questionable undertaking.