Abstract: (The Actor's Diary as the Art of Memory – A Different Kind of Biography) The actor's diary reveals the truth and it gives one the courage to write it down. The journal encourages self-discipline and mental organization. It puts a mirror in front of the eyes of its author and it helps one understand the inner fears and frustrations. The actors' diaries ultimately demystify a profession that many people see through rose-coloured glasses. Giulio Camillo's Memory Theatre was a utopian architectural system that promised to make universal knowledge visible. It was also meant to transform its sole spectator into rhetorician more skilled than Cicero. But that's precisely what theatre actually does - on a symbolic level. This is why the actor’s journal can be seen as a double mnemonic proces, extremly useful for both actor and reader.