This review elucidates state-of-the-art clinical studies on active specific immunotherapy with tumor vaccines. It refers solely to randomized studies and has a special focus on patient’s survival, the most important parameter for any therapy. Of special interest, from a tumor immunological point of view, is a comparison between the results obtained with allogeneic tumor cell-derived vaccines and those obtained with autologous tumor cell-derived vaccines. Overall, autologous vaccines have given better results than allogeneic vaccines. Random mutations in cancer generate unique antigens in each individual case. The superiority of autologous vaccines suggests that unique tumor-associated antigens are particularly important in generating responsive T cells for a therapeutic effect.