Research into the effects of fear-arousal on precautionary motivation and action is reviewed. Current models do not adequately distinguish between emotional (i.e., fear arousal) and cognitive (i.e., threat perception) responses to fear appeals and, in general, are not well supported. Evidence suggesting that (i) coping appraisals are more powerful predictors of precautionary action than threat perception and that (ii) fear control processes may interfere with precautionary motivation, recommends cautious and limited use of fear appeals in health promotion. It seems likely that fear arousal is less important in motivating precautionary action than perceptions of action effectiveness and self-efficacy. Moreover, perceived personal relevance may be critical to the emotional and cognitive impact of threat information. Available findings are summarised in the form of a process model that highlights the potential complexity of fear arousal effects. Sequential measurement of fear arousal, other than by self-report, is recommended in studies seeking to clarify these effects.