In this review we briefly discuss several central problems of modem oncoimmunology. We review the controversies surrounding the concept of immunological surveillance, as well as the problem of immunological tolerance to tumors. The discovery of tumor antigens has a great advance towards identification of possible therapeutic targets. However, antigen-specific vaccinations against cancer so far have a very limited use, mainly for prevention of virus-associated cancers, which is essentially based on anti-viral immune response. On the other hand, antibodies to cancer antigens are being widely used in cancer diagnostics, and there are remarkable examples of their therapeutic applications. The future opportunities in both theoretical and practical oncoimmunology will directly depend on further advances in basic science.