Cancer cells have developed numerous ways to escape immune surveillance and gain unlimited proliferative capacity. Currently, several chemotherapeutic agents and radiotherapy, either alone or in combination, are being used to treat malignancies. However, both of these therapies are associated with several limitations and detrimental side effects. Therefore, recent scientific investigations suggest that immunotherapy is among the most promising new approaches in modern cancer therapy. The focus of cancer immunotherapy is to boost both acquired and innate immunity against malignancies by specifically targeting tumor cells, and leaving healthy cells and tissues unharmed. Cellular, cytokine, gene, and monoclonal antibody therapies have progressively become promising immunotherapeutic approaches that are being tested for several cancers in preclinical models as well as in the clinic. In this review, we discuss recent advances in these immunotherapeutic approaches, focusing on new strategies that allow the expression of specific immunostimulatory molecules on the surface of tumor cells to induce robust antitumor immunity. © 2011 Wiley Periodicals, Inc.