Xenotransplantation, defined as the transplantation of animal derived organs and cells into humans, is currently a very active focus of research as it overrides some of the obstacles encountered with tissue engineering, such as vascularization and innervation. The resurgence of interest in xenotransplantation is mainly attributed to the improvement of gene editing techniques (such as CRISPR/Cas9), since genetically engineered animals have been generated to overcome organ rejection. However, xenotransplantation also raises multiple biological and ethical questions that should be taken into consideration.