Abstract: A new analysis of Émile Zola’s preparatory files reveals a discrepancy with the model of “program writing,” of which Zola was supposedly the paragon. The development of his practices over a long period of time, as well as the dual character of the files, written both for himself and as a showcase for methodical Naturalism, makes them appear as the site of experimental writing coupled with an ideal of perfection, or at least of a continuous, personalized, and high-quality learning process for the writer.