Lung cancer is now the leading cause of cancer deaths among women. In the United States, 64,300 women are expected to die of lung cancer in 1996. Smoking is responsible for about 80% of lung cancer cases. Unfortunately, the prevalence of smoking among women remains unacceptably high at about 22% and is expected to surpass the rate in men by the year 2000. Smoking rates are highest among young girls and the less educated. Whether lung cancer represents a different disease in women than in men is unclear. Data are conflicting regarding the magnitude of the relative risk of developing lung cancer due to smoking between the genders. There appears to be a difference in the relative distribution of lung cancer histologic features between men and women that is not explained entirely by differences in smoking patterns. Women who smoke appear to be at higher risk of developing small cell lung cancer than squamous cell lung cancer, whereas men who smoke have a similar risk for the two histologic conditions. Furthermore, women smokers are more likely to develop adenocarcinoma of the lung, and estrogens may play a causative role in this phenomenon. Data are unclear regarding whether the outcome of lung cancer treatment differs between genders. Solutions to the lung cancer epidemic among US women include (1) prevention of the disease by reducing smoking rates, (2) improving early detection methods, and (3) exploring new therapeutic strategies.