The Plan d'action en santé mentale 2005-2010 commands a substantial reform of mental health services organization. In order to achieve this, the Plan draws upon a set of ideas that appear somewhat unsubstantiated in regards to the sciences of organization. This article examines a few of these ideas. The managerial rhetoric of the Plan is anchored in an organizational and mechanistic archetype known for its inadequacy in the central mission of organizations of complex human services such as those concerning mental health. The mechanist rationality adopted marginalizes the real source of the value of mental health services, of practitioners and their social institutions. It participates in a movement that renders organizations always bigger, more abstract and impersonal steered from a distance by superficial indicators. There are good reasons to believe that this approach of organizational engineering will accentuate the eroding of the individual and collective capacities of delivering services of great value.