Clostridium difficile infection (CDI) is a major cause of infectious diarrhea and the most important cause of nosocomial diarrhea. Recurrent forms are a major problem with this infection. The use of fecal microbiota transplantation (FMT), FMT appears in the most recent European and North American recommendations. There is no cohort or multicenter registry in France prospectively collecting FMTs, the methods used, their efficacy and side effects. Likewise, there is no prospective collection focused on the cohort of stool donors. A large national cohort of patients who have undergone FMT as part of routine care as well as donors, is essential for evaluating the safety of FMT.