In order to evaluate postoperative pain treatment following thoracic surgery, 214 medical records of patients who were operated during 1986-1988 were examined. Nurses' comments concerning pain and the amounts of analgesics given during the 2 postoperative days were recorded. The 150 patients who were still alive in December 1989 were sent a postal questionnaire which asked about the pain and the efficacy of pain relief they had received after their operation. They were also asked if they still had pain which they connected to the thoracotomy and if any attempts had been made to treat that pain. The mean consumption of intramuscular oxycodone was 38 mg during the 1st and 33 mg during the 2nd postoperative day. The administration of nonsteroidal anti-inflammatory drugs significantly reduced the opioid consumption on the second but not on the first postoperative day. In 30% of the patients' charts there were no remarks on pain, in 10% there was a mention of no pain, in 40% pain was mentioned and in 20% the patient was reported to have severe pain. During the first postoperative week little pain was experienced by 60% of the patients, considerable pain by 35% and excruciating pain by 5% of the patients being interviewed. The postoperative pain relief was rated as good in 60% of the answers, satisfactory in 38% and poor in 2%. Persistent post-thoracotomy pain lasting for more than 6 months was reported by 44% of the patients, of whom 66% had received treatment for the pain.