This article is the result of an immersion in the archives of the School of Law of the University of Rome «Sapienza», searching for the most significant moments in Massimo Severo Giannini’s teaching of administrative law at that University. From the beginning, this call would prove to be problematic and would open a protracted period of discussion within the School’s assemblies, given the uncertainties that the former holder of the post Guido Zanobini expressed both about his physical conditions (which forced him out of academia for several years) and in the designation of who was to be his «heir» (Giovanni Miele, or Massimo Severo Giannini?). Invalid deliberations and bureaucratic intricacies, calls and abdications, questions of principles and political preferences, characterize the years of gestation of what would be a new beginning for the study of public law at the School of Law of the University of Rome «Sapienza».