Abstract:The aim of the current study is to evaluate new preventive command-and-control environmental regulation's competitive effects on automobile manufacturers and their suppliers. The methodology that we have used is a case analysis, and its main aim is to study an unfamiliar situation. Therefore, we have chosen cases from each of the groups: two suppliers and one manufacturer. The new regulation obliges automobile companies to deeply modify their process technologies and their relationships with their suppliers (toughening requirements and strengthening long-term relationships) and to require their workers to train in environmental matters. Complying with regulation by suppliers will be possible if product and process designs are modified. However, only organisational actions, which include workers' training in environmental and quality matters and activities to recover value in factories, are capable to achieve it. In any case, these factories have already been affected by trade-offs between environmental and other more classic manufacturing objectives, especially quality.