In recent years, an increasing trend has been recognized in the number of centers performing medical thoracoscopy across the world, mainly as a gold standard investigation for undiagnosed exudative effusion. It is a particularly useful diagnostic and therapeutic tool with a very low rate of complications that should be incorporated in the respiratory physicians’ armamentarium. Pleural biopsies under direct vision, therapeutic evacuation of effusions, and pleurodesis can be performed in one sitting. This chapter summarizes the important literature relating to the equipment, clinical indications, safety, complications and technical aspects of the procedure. We also aim to inform the reader regarding the latest research advances and potential areas of that MT will have a role in the future.