The aim of this prospective randomized trial was to compare the symptomatic effects of two different regimens of palliative radiotherapy for lung cancer. Two hundred and sixteen patients needing palliation were randomized to receive either a 17 Gy mid-point dose in two fractions 1 week apart or 22.5 Gy in five daily fractions. Both toxicity and efficacy were evaluated by postal questionnaires. This small study was intended to identify any clinically important differences in toxicity or efficacy between the two regimens. We detected no such difference, although there was a tendency for iatrogenic dysphagia and improvement in chest pain and cough to be more common with the two-fraction regimen. The only symptom that was improved in over 50% of patients for 8 weeks or more was haemoptysis. Haemoptysis and chest pain appeared to be the best indications for treatment. The relief of other symptoms was disappointing in both degree and duration.