Terror management theory argues that people can cope with the psychological threat of their own death by bolstering faith in their cultural worldviews. Based on the notion that-since the Age of Enlightenment-belief or faith in progress has become one of the defining qualities of modern Western thinking, we expected that this belief serves as a buffer against mortality concerns. Three experiments were conducted to test the relationship between existential anxiety and belief in progress. Results of Experiment 1 show that mortality salience increased participants' disagreement with an essay on the illusory notion of human progress. The same essay increased death-thought accessibility in Experiment 2. In Experiment 3, belief in progress and mortality salience were manipulated. Results show that bolstering belief in progress buffered the effects of mortality salience on death-thought accessibility and diminished subsequent defensive reactions to a cultural worldview-threatening essay.