This article focuses on the decision-making processes surrounding the implementation of Bill 25, Quebec's Act Respecting Local Health and Social Services Network Development Agencies. Our intention is to shed light on the strategies of the various groups or institutions that expressed their preferences and attempted, with varying degrees of success, to influence decisions with respect to this major reform of the Quebec health system structure. On a theoretical level, we are relying mostly on the models for analysing the lobbying process, which, since the seminal work of Milbrath (1960, 1963), have essentially presented this practice as a process for exchanging information. Based on the information gathered in the re-transcribed interviews, the strategies observed are actually in line with the constitutive characteristics of lobbying and, in some situations, those of patronage. Ultimately, the combination of these various elements makes it obvious that the implementation of Bill 25 was, first and foremost, a clearly political process. The technical arguments on which the initial objectives of the act were centred have thereby been relegated to the backstage.