Human lung transplantation was successfully performed in the early eighties and is now an option for patients with endstage lung disease, which is associated with poor survival. Most frequent indications for lung transplantation are emphysema, cystic fibrosis, fibrosing alveolitis, primary pulmonary hypertension and Eisenmenger's syndrome. Single lung transplantation (SLT) is most often performed in emphysema, fibrosing alveolitis and other diseases which are not associated with chronic infection of the lung. Double lung transplantation was recently replaced by the technique of sequential single lung or bilateral lung transplantation (BLT). Cardiopulmonary bypass can often be avoided and problems of the airway anastomosis are less frequent using BLT. Main indications for this procedure are cystic fibrosis, bronchiectasis and primary pulmonary hypertension (PPH). In PPH often only SLT is performed. Cor pulmonale is reversible following SLT or BLT even if the heart is not replaced. Combined heart-lung transplantation (HLT) is reserved for some cases of Eisenmenger's syndrome and few centers still prefer HLT in patients with cystic fibrosis. Patients are usually accepted for transplantation when they are considered to have life expectancy of 12 to 24 months. Quality of life and physical working capacity are severely decreased and patients suffer dyspnea NYHA grade III or IV. Most of the patients are hypoxic and need continuous oxygen therapy. Hypercapnia is also a negative predictive factor for survival without transplantation. In PPH cardiac index of less than 2 litres/m2 is associated with poor outcome. Not only absolute values for FEV1 and pO2 have to be considered in finding the best moment for assessment for transplantation but the clinical course of the disease during previous months and years also has to be taken into account. Contraindications to transplantation include acute infection, concomitant diseases of other organs, bronchial carcinoma and psychiatric disorders if noncompliance is likely. To achieve good results after lung transplantation, proper donor and recipient selection, experienced surgery and careful postoperative management are essential. Complications must be diagnosed early to provide effective treatment. Most complications occur within the first months after surgery. Early complications include primary organ failure, pleural bleeding, problems at the site of the airway anastomosis, infection and acute rejection. Acute rejection is common but can be treated successfully if diagnosed early.(ABSTRACT TRUNCATED AT 400 WORDS)