This thesis analyses competition and competition in supply chains. It focuses on the case of coopetition between an Original Equipment Manufacturer (OEM) and retailers, that collaborate in the forward supply chain and compete in the reverse. The thesis concentrates on the strategic options available to OEM in order to keep the remanufacturing operations of the retailer from eroding its market share. It analyses the impact that OEM strategic responses have on the environmental impact of the entire supply chain and each actor independently. The main contribution is in demonstrating the inherent trade offs in such a supply chain context. In attempting to abate competition, the OEM has a range of options available. It faces a stale mate: it can neither defend completely against competition, not improve substantially the environmental performance of the supply chain.