Globally, about three billion people use inefficient fires or basic stoves for their daily cooking, lighting, and heating. The smoke from these fires contributes to over 4 million avoidable deaths annually,i with women and young children the most affected. In this Part 2 of a 2-part series, Dr. Kalpana Balakrishnan discusses the health, safety, environmental, and economic implications of solid fuels in low and middle income countries.