Malignant pleural effusion is a frequent complication in many types of tumors, and its presence indicates short expected survival. This review updates the current knowledge about diagnosis and management of malignant pleural effusion. In recent years, progress has been made in diagnosis through the use of new pathologic and radiologic approaches, such as the introduction of positron emission tomography-computed tomography, immunohistochemical marker combinations, and genetic studies to identify malignant cells. Treatment is always palliative. New promising drugs have been tested, but, awaiting randomized studies, talc pleurodesis is still the treatment of choice, although doubts remain about its safety. A long-term indwelling pleural catheter could be a valid alternative to talc pleurodesis in selected patients with trapped lung syndrome (a lung that fails to reexpand after drainage of pleural effusion) and short life expectancy. However, the correct treatment depends on several factors such as performance status, expected survival, presence of lung reexpansion following pleural drainage and comorbidities.