We outline the determinants of local public policies for farmland preservation and urban expansion. We first rely on the literature and on a purposely designed field study of municipalities in southern France to propose a theoretical framework better suited to the French situation. The model considers aspects of land consumption, includes two interest groups as well as the median voter, and is then econometrically tested. We confirm the expected effects of certain sociodemographic determinants and highlight the impact of municipal budgetary considerations and the role of the agricultural sector. We also find more counterintuitive determinants, like local political regime or unbalanced neighboring relationships.