During the last two decades, improvements in the induction and consolidation treatment phases in patients with high-risk neuroblastoma have not translated into significant increases in survival rates. Efforts to improve outcome have used high-dose chemotherapy with stem cell rescue and more recently, differentiating (retinoids) and antiangiogenic agents. In parallel, immunotherapy has become an increasingly important part of the treatment of high-risk neuroblastoma. We review here the biological concepts underlying these new approaches and their clinical applications, with a particular emphasis on applications that manipulate the immune system, including monoclonal antibodies, gene-modified tumor cells (vaccines) or immune effectors.