Exposure to secondhand smoke (SHS) from burning tobacco products causes sudden infant death syndrome (SIDS), respiratory infections, ear infections, and asthma attacks in infants and children, and coronary heart disease, stroke, and lung cancer in adult nonsmokers. No risk-free level of SHS exposure exists. SHS exposure causes more than 41,000 deaths among nonsmoking adults and 400 deaths in infants each year, and approximately $5.6 billion annually in lost productivity. Although population exposure to SHS has declined over the past 2 decades, many nonsmokers remain exposed to SHS in workplaces, public places, homes, and vehicles.