Abstract The occupants of all buildings have a right to healthy indoor air. However the air in buildings can contain a range of pollutants that adversely affect the cardiovascular, endocrine, immune, nervous, and respiratory systems of the human body. Exposure lowers physical and mental health, well-being, and productivity with social, political, and economic consequences. Providing plenty of fresh air is not always a solution because it has energy and carbon penalties. This article highlights the benefits of acceptable indoor air quality, and provides methods of identifying exposure to pollutants and controlling them to keep occupants of buildings, happy, healthy, and productive.