In France, the ending of milk quotas marks a breach in the mode of milk supply management and dairy farmers' conditions. Regulation administered by public authorities gave way to private regulation by dairy companies. In this context, farmers and actors of territorial development are concerned about the future of dairy farming at local scale. This paper explores the effects of ending milk quotas at the local level by comparing two contrasting case studies: upland and lowland areas. It is based on the same conceptual framework of socioeconomic metabolism, which addresses the biophysical exchange relationships between societies and their natural environments. We sought a better understanding of the effects of ending milk quotas, through looking at milk flows and uses of local resources, and the system of actors activating and regulating these flows, and their strategies. Our research is based on interviews and presentations of our characterization of milk production designed to prompt discussions between farmers and local actors. We show that the ending of milk quotas, and the ensuing high price volatility, means increased disparities between farmers. It generates (i) in the upland area, rivalry and tensions at the local level, and (ii) in the lowland area, difficulties in sustaining cow milk production in an area that is turning towards crop production. Lastly we discuss, among other topics, the multidimensional and growing requirements and systems boundaries that farmers are facing.