A study of the relative economics of different approaches to reducing greenhouse gas emissions offers surprising insights for policy makers and business leaders. For starters, in a 25-year perspective, power generation and manufacturing industry offer less than half of the potential for reducing emissions. Almost a quarter of possible emissions reductions would result from measures (such as better insulation in buildings) that carry no net life cycle cost - in effect, they come free of charge. The study finds that a substantial share of the overall opportunities, including large potential to reduce emissions by protecting and replacing forests, lies in developing economies. Author: P. Enkvist, T. Naucler, and J. Rosander (McKinsey); Year: 2007