Female lung cancer death rates increased by more than 550 percent between 1950 and 1991. In 1986 lung cancer surpassed breast cancer to become the leading cause of cancer death in women in the United States. The lung cancer epidemic is primarily attributable to cigarette smoking, which is responsible for at least 80% of the disease in women. There are gender differences in the distribution of lung cancer by histologic type, even controlling for smoking, and some data suggest greater female than male susceptibility to lung cancer at a given level of smoking. Exposure to environmental tobacco smoke increases risk of lung cancer in nonsmoking women. Family history of lung cancer, personal history of lung disease (e.g. asthma, chronic bronchitis, pneumonia, or tuberculosis), and a history of radiotherapy also appear to be associated with increased risk. Data specific to women on the role of household radon exposures or of specific occupational or environmental exposures are relatively sparse and inconsistent. Finally, many studies have reported a decreased risk of lung cancer in individuals who consume high levels of fruits and vegetables; however, clinical trials fail to support a beneficial effect of beta-carotene supplementation. Since cigarette smoking accounts for the vast majority of lung cancer cases in women, efforts to prevent adolescent girls from starting to smoke and to encourage cessation among established smokers have the greatest potential for reducing the female lung cancer burden.