British Petroleum (BP) has pledged to reduce its emissions of greenhouse gases by 10% by 2010 from a 1990 baseline. "We'll do that progressively, year by year. And we'll do it in transparent ways, so the reduction can be measured and verified by external observers," BP's Chief Executive Sir John Browne told students at Yale School of Management in September. Cuts in BP's emissions will come from a range of developments including new pipeline technology, more efficient energy use and by eliminating flaring. To achieve its target at the lowest cost, BP has introduced a pilot emissions trading system within the company involving 12 of its business units. This will allow the business's particular fields and refineries to take a share in the overall target and find the cheapest way of meeting it. If successful, it will be extended to the rest of the group. The company is also exploring other mechanisms, such as joint implementation, carbon sequestration and technology transfer, said Browne.