Adjuvant chemotherapy and hormonal therapy reduce the risk of recurrence and death due to breast cancer, but often at considerable cost to the health-related quality of life (HRQL) of patients. The short-term effects of chemotherapy on HRQL are well known and are accepted by most patients for modest gains in survival. The long-term effects of chemotherapy-induced menopause and hormonal therapy on HRQL are poorly recognized. Vasomotor symptoms and altered sexual function are common, distressing and inadequately treated. HRQL information is helpful in describing likely effects of adjuvant treatment, facilitating informed decision-making, identifying health problems to guide research into potential solutions, guiding treatment strategies for interventions with equivalent survival and guiding resource allocation. New technologies will make HRQL information increasingly available for individual patient care.