This article describes a systemic approach to analyzing issues related to food and eating, starting with a review of the different meanings and uses of the notions of food systems and agri-food chains. A systemic, multi-scale approach is developed to support the proposed notion of decentralized food systems in an attempt to account for the complementarities, conflicts, and hybridisms that result from the coexistence of distinct food systems in terms of modes of production and distribution, flows of goods, and the shaping of eating habits. Special attention is paid to localities and respective territories as analytical spheres, with the introduction of empirical evidence from two studies conducted in the Brazilian localities of Juazeiro (Bahia) and Chapecó (Santa Catarina).