In several countries, genetically modified organisms (GMOs) are grown under a deregulated regime, while in others they are regulated by the legislation required for a new GM crop. In these latter countries, due to concerns of citizens and consumers, GMOs and their derived products are labeled and traced to ensure consumers have their right to choose. Accordingly, GM crops are subject to a coexistence scheme with non-GM crops (i.e., conventional and organic supply chains). While the coexistence downstream of silos is relatively easy, and well mastered by companies, the coexistence from seed production to the silos is still a matter of debate and pending implementation. This entry presents the pros and cons of two different crop coexistence concepts, i.e., flexible and agricultural dedicated production area (DPA)-based coexistence. It addresses biological and economic issues, including territory organization by downstream supply chains, as well as societal issues raised by coexistence.