Malignant pleural mesothelioma (MPM) is a rare cancer with a poor prognosis. The disease is of importance, since the incidence in Denmark is increasing despite cessation of the use of asbestos in the 1980s. MPM has a long latency period, and the first symptom is often dyspnoea, typically caused by pleural effusion. The diagnosis is a challenge, because cytology often is non-conclusive, and thoracoscopy is needed to obtain biopsies for immunohistochemistry. The occupational history is important, since the patients are entitled to compensation. The treatment is often limited to palliation.