The incidence of mesothelioma continues to increase in the Western world and is likely to do so until 2011-2015. It commonly presents with breathlessness secondary to a pleural effusion, and whilst guidelines still advise thoracocentesis as the first line investigation, the sensitivity of this is low and a tissue diagnosis is usually required. Abrams needle biopsy also has a low diagnostic yield and high complication rate and is not recommended in guidelines on the investigation of mesothelioma. Computed tomography-guided biopsy or thoracoscopy both have a comparable sensitivity and low complication rates. Local anaesthetic thoracoscopy is increasingly used by respiratory physicians and has a comparable diagnostic sensitivity to Video-Assisted Thoracoscopic Surgery (VATS) without the need for a general anaesthetic. The requirement for prophylactic radiotherapy after pleural procedures in cases of mesothelioma is contentious, as the results from early trials suggesting it reduces tract seeding have been disputed by more recent trials.