Data from 303 patients with 389 admissions for spontaneous pneumothorax from 1970 to 1980 at Ullevaal Hospital, Oslo, Norway, were reviewed. Spontaneous pneumothorax carried a significantly higher complication and mortality rate in patients suffering chronic obstructive pulmonary disease (COPD). Their higher median age compared to non-COPD patients contributed to this, but did not account for the increased mortality. The risk of developing wound infection and/or pneumonia was significantly higher after 7 days of chest tube treatment in both patient groups, independent of age. There was no association between recurrence rate and COPD/non-COPD, age or duration of chest tube treatment (1-7 days, 8 days or more). Complications were not more frequent after thoracotomies performed in COPD patients. Therefore operative treatment for both primary and COPD-related spontaneous pneumothorax should be considered if tube treatment is not successful after 1 week and there are no contraindications.