and materials, combined with the construction of more air-tight buildings, began to generate health costs that could be ignored no longer. Air pollution is now typically two to five (and sometimes a thousand) times higher indoors than outdoors. In North America, over 60 million people suffer from asthma, allergies, respiratory disease, and various illnesses associated with indoor air pollution. Health symptoms are experienced by 20 to 30 percent of office workers. Besides serious respiratory and nervous system damage, millions experience more mild symptoms like headaches, nausea, dizziness, short-term memory loss, irritability, and itchy eyes and throats (Black & Bloech, 2002). The US Environmental Protection Agency (EPA) estimates that indoor pollution is responsible for more than 11,000 deaths each year from cancer, kidney failure, and respiratory collapse (Ligon, 2001). 50 percent of all schools have IAQ problems. 7.5 million Americans have asthma, and doctors have linked the doubling of asthma rates since 1980 to bad indoor air (Conlin & Carey, 2000). A new medical phenomenoncalled multiple chemical sensitivity (MCS)has devastated the lives of thousands of people whose overburdened immune systems react to even the smallest amounts of many different substances. Researchers have found that chemicalized air even leaves a film on office equipment that reduces its durability (H. Baker, 1997). Cost-cutting externalities for some industries have become expensive burdens for others, with bad-air illness now estimated to cost US corporations over $60 billion annually. According to researchers at Californias Lawrence Berkeley National Laboratory, US companies could not only save that $60 billion by preventing sickbuilding illnesses, but they could also could generate an additional $200 billion in worker