A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was 'For patients with malignant pleural effusion is chemical pleurodesis with povidone-iodine as effective, safe and well tolerated as talc pleurodesis for prevention of recurrent malignant pleural effusions?'. A total of 124 papers were found during the search, of which 8 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group studied, study type, relevant outcomes and results of these papers were tabulated. At present, Talc monopolises the pleurodesis market due to the extensive clinical history and well-known side-effect profile rather than superiority alone. However, studies using povidone-iodine seek to challenge this showing equality, efficacy and improved cost efficiency. As such, it is remiss to continue to recommend a single agent exclusively when isolated superiority is no longer apparent.