The median age at diagnosis of patients with lung cancer is currently around 70 and is rising, yet the trials on which treatment is based included few elderly people. We conducted a prospective observational cohort study of 83 elderly patients (aged 75 and above) being treated with palliative radiotherapy for lung cancer, with a comparison group of 49 younger patients (aged 65 and under). Response to treatment was evaluated by patient-assessed symptom and quality of life scores using the EORTC QLQ-C30 and its companion lung module LC17. This is to date the largest prospective study of elderly lung cancer patients in routine practice. We found no significant differences in response or toxicity between the two groups. Elderly people with lung cancer should be offered palliative radiotherapy the same as younger patients, with the same expectation of benefit.