Advanced non-small cell lung cancer (NSCLC) in elderly patients is an increasingly common problem which the practitioner of oncology must face. There is no consensus on the cut-off age for defining the elderly. However, 70 years may be the most appropriate because the incidence of age-related changes starts to increase after this boundary. Important concerns in evaluating the treatment of elderly patients are the presence of comorbidities and the progressive physiologic reduction of hepatic, renal and bone-marrow functions which could have a negative impact on the degree of toxicity. To individualize treatment choice within a group of elderly NSCLC patients of the same chronological age, it would be important to perform a comprehensive geriatric assessment (CGA) which would allow to subdivide elderly patients into three main categories: fit, pre-frail and frail. Fit older patients have similar prognosis and a similar treatment tolerance and outcome compared to their younger counterparts. On the other hand, pre-frail patients experience significant treatment related toxicity and usually are offered a single-agent chemotherapy whose choice should take into account the expected toxicity profile of the agent, pharmacokinetics, organ function and co-morbidities. For the third category of patients only best supportive care or individualized approaches are recommended.Overall, only prospective trials, specifically addressed to elderly NSCLC patients selected through an adequate CGA at baseline, let us opt for the best treatment to be administered to each elderly patient.