Quality-of-life evaluation has gained increasing attention within the oncology community over the past 2 decades. The breadth of quality-of-life research in women with breast cancer has expanded substantially during this time. This paper reviews the status of quality-of-life research in women with breast cancer and explores several areas in which quality-of-life research can be of value. Descriptive quality-of-life studies in patients undergoing active treatment can identify the impact breast cancer treatment has on a patient's life. For patients who have completed treatment, research can detect areas of persistent distress. Quality-of-life assessment now is incorporated in many clinical trials. These data can provide a patient-rated assessment of treatment and complement the traditional endpoints in clinical trials. Examples of selected quality-of-life studies in patients with breast cancer are presented.