Pleural effusions associated with malignancy--either malignant or paramalignant diseases--were found in ca. 20% of these patients. Large pleural effusions cause mainly dyspnoea but also cough and chest pain. The presence and degree of dyspnoea depend on the size of the effusion and the patient's underlying pulmonary function. In acute cases and large effusions immediate chest drainage is indicated in symptomatic patients, followed by the treatment of the underlying disease, e. g. chemotherapy. The most effective therapy for controlling reiterated malignant pleural effusions is the thoracoscopic talc poudrage (2.5-10 g) which has been shown to have a success rate of > 90%. Talc induces a broad inflammatory reaction involving mesothelial cells of the pleura, coagulation parameters, fibroblast proliferation eventually leading to symphysis of the pleura. This procedure is reserved for patients who are in good general conditions, who are expected to have a reasonably long survival, and who failed chemical pleurodesis. A good predictor for longer survival time is a Karnofsky Performance Scale > or = 40 indicating a survival time > 30 days, which therefore should be considered prior to the procedure. The adult respiratory distress syndrome (ARDS) is the most important complication initially observed in the US in up to 9% of all cases. ARDS incidence was strongly related to high number (50%) of small talc particles < 15 microm. In summary, talc poudrage or slurry (talc particle size > 10 microm) in malignant pleura effusions is a safe and effective method to induce pleura symphysis. Complaints and complications such as chest pain, transient fever, and empyema are rare or very are which are almost exclusively related to the therapeutic procedure itself.