With help from the Environmental Defence Fund, an American lobbying group, it has also launched an experiment in emissions trading within the firm to help it reach that target.

ECONOMIST: Environmental policy: Hot market | The

Chris Graff, of the Environmental Defence Fund in Oakland, notes that advocates of new water projects become much less enthusiastic if it is proposed that the users pay for it.

ECONOMIST: Water policy

As companies seek to win credibility for their efforts at reducing emissions, they are inviting mainstream green groups such as Washington's Environmental Defence Fund to advise them and to keep them honest.

ECONOMIST: Emissions