Nietzsche did not write a completed magnum opus, a ‘Hauptwerk’, but he planned to do so during at least the last 5 years of his active life. I will show that during and after the writing of Also sprach Zarathustra this was his main aim and ambition. The projected work passed through a number of related phases, of which the much discussed and controversial ‘Will to Power’ was merely one. This intention to write a magnum opus has been denied or (...) almost completely ignored by almost all commentators . I will bring attention to this intention, discuss why it has been ignored and show that an awareness of it is important for our understanding of the late Nietzsche's thinking and for determining the value and originality of his late notes. It has been a failure of historians of philosophy, intellectual historians and Nietzsche scholars not to have taken this into consideration and account. (shrink)