Today several monoclonal antibodies, including the anti-CD20 antibody (rituximab), the anti-CD52 antibody (alemtuzumab) and the anti-CD33 antibody (gemtuzumab ozogamacin) are all integrated in the therapeutic armamentarium of patients with malignant lymphoma, chronic lymphocytic leukaemia and acute myelogenous leukaemia, respectively. Rituximab has also been shown to be highly effective in the treatment of refractory autoimmune haemolytic anemias, idiopathic thrombocytopenia, and relapsing thrombotic thrombocytopenic purpura. New signal transduction inhibitors, dasatinib and nilotinib, are being used in patients with chronic myelogeneous leukaemia who develop resistance to imatinib. Thalidomide, lenalidomide and bortezomib have all been shown to be highly effective in multiple myeloma, and JAK2-inhibitors have entered phase II studies of patients with JAK2-positive primary myelofibrosis and related diseases.