Cancer is the leading cause of death in women and men aged 60 to 79 years. The biologic characteristics of certain cancers are different in older patients compared with their younger counterparts, and older patients also have decreased tolerance to chemotherapy. Nevertheless, advanced age alone should not be the only criteria to preclude effective cancer treatment that could improve quality of life or lead to a survival benefit in older patients. Treatment should be individualized based the nature of the disease, the physiologic status of the patient, and patient preferences. Chronologic age is not reliable in estimating life expectancy, functional reserve, or the risk of treatment complications. Whether cancer treatment is appropriate may be best determined through careftil assessment of the older patient. CGA can be used to assess life expectancy and risk of morbidity from cancer in elderly patients, in turn enabling physicians to develop a coordinated plan for cancer treatment and guide interventions tailored to the patient's problems. © JNCCN-Journal of the National Comprehensive Cancer Network.