In multilingual legal systems, different language versions of legal texts are considered legally equivalent. This master’s thesis deals with the process of multilingual legislative drafting and the institutional translation practices within the Swiss federal administration that lead to this particular form of equivalence. The aim is to account for the complexity of this process, which is based on a variety of drafting, translation and revision actions carried out by linguistic specialists and jurists with heterogeneous skills. This work studies the parallel genesis of the German and French versions of an ordinary law with the theoretical and methodological tools of the Actor-Network Theory. It proposes an integral mapping of the process of multilingual legislative drafting, presents the various professional profiles that participate in it and describes the multiple practices of language transfer that are part of it.