Although mostly resistant to cytotoxic therapy, renal cell carcinoma has been a testing ground for immunotherapy. The approval of interleukin-2 for the treatment of renal cell carcinoma was a landmark "proof of principle" which showed that agents working solely via the immune system can cause durable cancer remission. Dendritic cells are central to immune-mediated surveillance and destruction of abnormal cells. They possess all the components required to educate immune effector cells that can then mediate tumor destruction. In vitro strategies to expand and load dendritic cells with antigens have now led to human vaccine trials in renal cell carcinoma and other malignancies.