Indoor air pollution (IAP) is one of the major risk factors for pneumonia related morbidity and death in children world-wide. It is also associated with other adverse health outcomes in children such as low birth weight and chronic bronchitis, and with lung cancer, cataract and possibly cardiovascular disease in adults. Biomass fuel (wood, crop residues, animal dung) which is being used in four fifths of all households in Pakistan is the major source of IAP when it is burned for cooking, space heating and lighting homes. Biomass is mostly burned in inefficient three-stone stoves leading to incomplete combustion and high levels of indoor air concentration of smoke. There is a dearth of scientific studies in Pakistan to relate IAP to health effects; consequently IAP is not a recognized environmental hazard at policy level.