Recent advances in understanding of fundamental immunology have created new insights into the dynamic interactions between tumors and the immune system. This includes new understanding of T- and B-cell interaction, immune inhibitory mechanisms including the biology of T regulatory cells, myeloid suppressor cells, and dendritic cell subsets. Enhanced understanding of mechanisms underlying T-cell anergy such as arginine deprivation, immunosuppressive cytokines, defective innate and interferon response pathways, and NKG2D downregulation have all provided new insight into suppression of anti-tumor immunity and tumor evasion. In addition to emerging understanding of tumor evasion, new immune targets such as CTLA4 blockade, NK stimulatory receptors, manipulation of the antigen processing and presentation, cytokine and costimulatory responses all provide new possibilities for enhancing anti-tumor immunity even in tumors previously felt to be resistant to immune attack. Several of these strategies have already been realized in the clinic. The volume will explore evolving paradigms in antigen presentation, dendritic cell biology, the innate response and immunosuppressive mechanisms, and emerging strategies for manipulation of the immune system for therapeutic benefit that have realized success in neuroblastoma, leukemia, melanoma, lung cancer, and allogeneic transplantation. Early successes as well as failures will be highlighted to provide a snapshot of the state of clinical immunotherapy with an eye to future possibilities such as combination therapies, adoptive T-cell transfer, and the retargeting of immune cells via T-cell receptor engineering.