BACKGROUND--Primary tracheal tumours are rare, so few physicians have extensive experience of their management. No direct comparisons have been made of surgical and radiotherapy treatment. METHODS--A postal survey of cases presenting in the last 10 years in the United Kingdom was conducted. Results were expressed as cumulative survival and survival curves were compared by the log rank test. RESULTS--Three hundred and twenty one patients were recruited. Overall five year survival rates were 25% for squamous cell carcinomas, and 80% for adenoid cystic carcinoma; 62% received radiotherapy but only 10% underwent surgery. Small cell carcinoma was more common than expected with an incidence of 6%. In patients with squamous carcinoma improved survival was seen in those with tumour in the upper trachea. High dose radiotherapy was more effective than low dose only in tumours of the upper trachea and in squamous carcinoma. In adenoid cystic carcinoma no significant difference in survival rate was seen between treatment with radiotherapy and surgery. No histological diagnosis was made in 44 patients, the most common reason being fear over the safety of fibreoptic bronchoscopy; however, this group had a cumulative survival at five years of 46%. CONCLUSIONS--Survival may be somewhat better in cases with tracheal tumours than in those with bronchial tumours. Small cell carcinoma is less rare than was previously thought. Upper tracheal tumours may merit more aggressive therapy. It is important to make a histological diagnosis even if rigid bronchoscopy is necessary, and referral to specialist centres is recommended. A larger prospective study is required to compare the value of surgery and radiotherapy.