GVHD continues to be a major complication after allogeneic hematopoietic stem cell transplantation even when the recipient is given immunosuppression for the prophylaxis of this severe disease. There have been many advances in the prevention and treatment of GVHD, using compounds such as cyclosporine, FK506, mycophenolate mofetil or monoclonal IL-2 receptor antagonist. New strategies seem to include sequential therapy involving the blocking of both endogenous cytokines and alloreactive donor cells. However, further clinical and laboratory studies are needed in order to improve the therapy of established GVHD.