In order to assess their reaction to the information given, 50 patients underwent a semi-structured interview with a social worker within 1 week of having been told the diagnosis of lung cancer. There were 32 men and 18 women with a mean age of 63 (range 38-82) years. Thirty-eight (76%) belonged to Registrar General social class IV or V, and 45 (90%) had left school at the age of 15 years. Two patients were unaware of the diagnosis despite having been told that they had lung cancer. Two patients would have preferred not to have been told the diagnosis and two were unsure, while 46 (92%) felt that telling them the diagnosis truthfully had been correct. No patient felt that they had been given too much information, but 13 (26%) indicated a lack of information about prognosis. Despite being told 'bad news', 31 (62%) felt more reassured after their interview with the doctor, 5 (10%) felt less reassured, and 14 (28%) were uncertain. Twenty-one (42%) patients were experiencing a sense of guilt or regret at having smoked. Many patients had concerns about specific symptoms which they expected to suffer. In general, patients wanted to be told their diagnosis truthfully and required a high level of information. Many patients felt reassured by the discussion of such details.