Outsourcing is considered as a key factor for optimizing cost-efficiency and reinforcing competitiveness within supply-chain. This chapter investigates the outsourcing from forward-loop and reverse supply chain. We address a single manufacturer in relationships with an upstream partner encompassing a raw material supplier and subcontractors with cutting-edge technology. Meanwhile, downstream partners consist of subcontractors’ collection centers that deal with returns. The manufacturer involves subcontractor contracts for purchasing ready-to-use products besides leveraging comparative advantage. The latter focuses on returned products, with in-house remanufacturing and outsourcing. Outsourcing is justified by capacity and specific process requirements. A multi-objective mixed integer programming formulation is proposed and implemented thanks to GAMS software for the elaboration of an integrated plan minimizing economic costs, carbon emissions, and system unavailability. On this basis, computational experiments reveal the benefits of integrated manufacturing/remanufacturing/outsourcing with CO2 emissions reduction in decreasing new product demand, which results in major resource savings.