Within the sustainability arena, CO2 reduction has emerged as a key challenge for manufacturers in the fast-moving consumer goods industry. This goal needs to be balanced against the competitive priorities of cost and responsiveness. Emissions-reducing efforts are driven by the need to comply with expectations from industry and end customers and by opportunities for energy and cost savings. Manufacturers are now looking beyond their corporate boundaries to find new ways to reduce emissions along the supply chain. There is a need for research to address supplier selection in the face of sustainability challenges and provide insights about the factors affecting the transfer of sustainability skills between the manufacturer and its suppliers. This multiple case study investigates the factors that influence an organization's readiness to engage in a collaborative CO2 reduction management (CCRM) approach. We find that partner selection for CCRM exhibits path dependency in terms of the manufacturer's maturity level of sustainability; characteristics of key downstream customers, in turn, are shown to also impact this selection.