Air pollution in big cities gets headlines, but in many rural areas of developing countries indoor air pollution is an even more serious health problem. Poverty condemns half of humanity to cook with solid fuels on inefficient stoves. As a cause of ill health in the world, indoor air pollution ranks behind only malnutrition, AIDS, tobacco, and poor water/sanitation.Smoke in homes from these cook stoves is the fourth greatest risk factor for death and disease in the worlds poorest countries, and is linked to 1.6 million deaths per year. Yet the international community has largely neglected it....