In medicine, transferring human material from one individual to another is called transplantation. Despite the equivalence of the term “transplantation” and the complexity of the underlying legal regulations, a firm distinction must be made between the transplantation of stem cells and that of other organs and tissues or other body parts. Stem cells are a regenerative tissue in the body which are taken from a specifically selected donor – usually an adult. As a complete immune system is transplanted rather than normal body cells only, the requirements for an HLA match are much higher and the medical conditions far more complex (allogeneic transplantation, autologous transplantation).