While the immune system attempts to constrain tumor growth, tumor cells often escape this immune pressure, in a manner similar to tumor cell evasion of classic tumor suppression mechanisms. The dual host-protective and tumor-promoting actions of immunity are referred to as cancer immunoediting. Cancer immunoediting emphasizes that extrinsic immune pressure either can block tumor growth, development, and survival or can facilitate tumor outgrowth by shaping tumor immunogenicity and inhibiting host-protective antitumor responses. In this webinar, Nir Hacohen and Robert Schreiber discuss recent advances in our understanding of cancer immunoediting and the implications for cancer immunotherapy.