Thalidomide has antiangiogenic and immunomodulatory properties and has recently been used in the management of human malignancies. Multiple studies have confirmed its activity in multiple myeloma, alone or combined with dexamethasone and/or chemotherapy as first- or second-line treatment. In addition, it may reduce the need for transfusions in patients with myelofibrosis or myelodysplastic syndromes. The activity of thalidomide in solid tumours is less prominent. The most promising results have been reported in Kaposi's sarcoma, malignant melanoma and prostate cancer, especially when it is combined with chemotherapy. Recently, thalidomide analogues (immunomodulatory drugs), with higher immunomodulatory activity and different toxicity profile, have been developed. They have already shown promising activity in multiple myeloma and are currently being evaluated in clinical studies.