The research investigates the role the environmental manager plays to ensure a successful (or not) implementation of environmental performance within an organization. It is based on interviews of 5-7 actors per company within a sample of 7 companies (42 interviews). We build upon bias of perception of the various actors interviewed within each company to define 4 paradoxes related to the roles and mission of the environmental manager that hinder proper efficiency of environmental management at company level. Paradox 1 is that no one takes ownership of environmental performance within the organization. Paradox 2 is that the environmental manager is in an awkward situation vis-à-vis his boss. Paradox 3 is that the role of the environmental manager is ambiguous vis-à-vis employees. Paradox 4 is that corporate and product approaches are decoupled. We suggest that these paradoxes interact and form a vicious cycle that may in part be responsible for the environmental decoupling phenomenon – the fact that companies often adopt a sustainability policy symbolically without implementing it substantively. Our research suggests that, by leveraging the leadership of the environmental manager through organizational and motivational measures, the vicious cycle can be transformed into a virtuous cycle and the human motivation can become a driver for green change within corporations. We proposed the SEA (Shaping Environmental Action) model based of 4 pillars: information, motivation, organization and strategy.