Burnout has traditionally been thought to result from unrealistically high expectations although research has provided only equivocal support. We explored the impact of cognitive adaptation disposition, including mastery, optimism, and self-esteem, on the expectations–burnout relationship. Nurses (N = 341) who were recruited at professional conferences completed questionnaires that assessed cognitive adaptation, burnout, and initial and current expectations of control. As expected, cognitive adaptation predicted fewer unmet expectations of control, which in turn predicted lower burnout. In addition, optimism and self-esteem predicted lower burnout regardless of perceived initial expectations, whereas mastery lessened the negative consequences of initially high expectations on burnout.