This paper reports an experimental study investigating the role of cognitive factors and fear in mediating the effects of "fear-arousing" health threat communications. Seventy-seven cigarette smokers were shown either a videotape about smoking or a control videotape on a different health topic before completing a questionnaire assessing their intentions to try to quit, the level of fear aroused, and three cognitive factors: (a) probability difference (perceived reduction in risk of health damage that follows from successful cessation), (b) utility of health damage, and (c) confidence. The smoking videotape influenced probability difference, utility, intentions, and follow-up reports of attempts at cessation. As predicted, both probability difference and utility influenced intention, which in turn influenced behavior. Neither confidence nor the amount of fear aroused by the videotape had significant effects on intention.