Recently (282, 288), the authors in their opinion pieces have argued that “functional adaptation” would be a more appropriate term for T-cell “exhaustion” as CD8+ T-cells may continuously adjust their differentiation states in response to sustained antigen exposure to better meet the needs of the body during a chronic infection by maintaining viral control without causing overwhelming immunopathology and the same would apply to cancers as well. The gene discussed is CD8A; the disease is cancer.