This paper reviews recent advances in the methods for assessing the quality of life of patients with lung cancer and recent applications of quality-of-life measures in lung cancer clinical trials. In terms of methodology, there exist today a number of self-report quality-of-life questionnaires that are valid, reliable, and sufficiently brief to be of practical use in clinical research settings. Application of these measures in lung cancer clinical trials has contributed to the evaluation of: 1) long-versus short-duration chemotherapy, four- versus two-drug combinations, intensive versus standard chemotherapy, and continuous versus bolus injection chemotherapy in the treatment of small cell lung cancer; 2) high versus low radiation doses in the treatment of non-small cell lung cancer; 3) megestrol acetate and hydrazine sulfate as supportive treatment for small cell lung cancer and non-small cell lung cancer patients receiving chemotherapy; 4) granulocyte colony-stimulating factor in small cell lung cancer patients receiving dose-intensified chemotherapy; and 5) the rehabilitation needs of lung cancer survivors. Future efforts should be directed toward achieving higher levels of compliance with clinical trial-based quality-of-life studies, and the development of techniques for integrating quality of life and clinical outcomes for purposes of cost-effectiveness evaluations.