For eligible patients, the value of immunotherapy for metastatic clear-cell renal cancer is its curative potential, as demonstrated by long-term follow-up after interleukin-2. Advances in cellular therapies, manipulation of activating and inhibitory receptors on T cells and modification of allotransplantation regimens have all produced new tumor regressions in patients who did not respond to conventional interleukin-2 regimens. It is clear that renal cancer remains one of the most immunoresponsive of human malignancies and that advances in immune modulation are again translating into clinical responses for patients with this disease. As the array of biologic therapies for renal cancer expands with the approval of tyrosine kinase inhibitors, immunotherapy, the only modality that can cure widespread renal cancer, must not be overlooked.