Summary: The potential use of intestinal fecal microbiota transplantation in the treatment of various diseases and ailments has long aroused interest. Until now, the only disease entity in which the beneficial effect of intestinal flora transplantation has been proven is Clostridium difficile infection. Recently, due to access to new diagnostic methods and the ability to identify microorganisms that cannot be dislodged in a conventional manner, knowledge about the intestinal microbiota and its disorders has increased significantly. This has resulted in numerous studies to assess the efficacy and safety of intestinal flora transplantation also in other diseases, the etiopathogenesis of which depends in part on disturbances in the composition of the microbiome.