Conventionalisation" hangs like the sword of Damocles over organic farming. Raised by certain agrobiologists, the threat has been examined by researchers who have attempted (with little success) to measure any shift in how organic standards are put into practice. This article takes up the issue, but instead of trying to make explicit what is meant by organic (a difficult task in light of the variety of interpretations) as earlier research has done, it attempts to enter into the controversy surrounding the development and sustainability of the movement. This investigation illustrates the opposition between two regimes of action, each based on very different visions of the acceptable use of the AB label: the first tends to reduce organics to a set of regulatory restrictions imposed by the label, while the other sees these restrictions as a reductive and insufficient framework. For this regime, organic production is more than just a set of restrictions. It is instead a "philosophy" or "spirit" guiding a broad examination of the production process and its result. Nevertheless, despite their disagreements, the two regimes are also in close and mutually-beneficial interaction. Two contradictory characteristics of organic production emerge, thus ensuring its sustainability: its capacity to spread through economic networks thanks to a more rigid framework, and its flexibility that enables it to continually redefine itself and adapt to new situations.