The present paper describes eight patients (two teenagers and six adults) who had chronic symptoms (haemoptysis, cough, recurrent pneumonia) caused by foreign body (FB) inhalation which went undetected for 3 months to 25 yr. None of the patients had the usual predisposing conditions like mental retardation, seizures or brain tumour. The diagnosis of FB was made by radiography in one patient only. Computerized tomography visualized one FB (a beef bone), and bronchoscopy identified FB in another two patients. The remaining four cases were diagnosed at thoracotomy. Removal of FB was curative in three of five cases who required surgical resection for irreversible bronchiectatic changes. The severity of pulmonary changes correlated with duration of symptoms. It is concluded that chronic, unexplained respiratory symptoms should warrant further investigation to exclude FB despite negative history and normal chest radiography. Finding of granulation tissue or cicatricial stenosis of the bronchus could be the only clue to the presence of a FB. Early diagnosis would avoid irreversible parenchymal changes which necessitate lung resection.