An advertising experiment was conducted to test the advertising wearout of four anti-speeding ads, each with varying underlying "patterns" of fear arousal. The patterns of fear were established beforehand by using a dial designed to track viewers’ reactions in terms of tenseness felt. The advertising experiment involved 284 participants from a first-year University marketing class. Four experimental groups were exposed to the same antispeeding ad each week, for three sequential weeks. Measures were obtained, via a questionnaire, of the participants’ attention paid to the ad, expected effect on speeding behaviour, emotions felt, perceptions of the relevance, believability, realism of the ad, and demographic and driving history. The groups comprised participants with homogenous demographic characteristics (with the exception of gender) and driving histories, thus allowing the different mean scores of various effectiveness measures to be attributed to the ads themselves rather than the differences between the participants’ characteristics. Repeatedmeasures analysis of covariance (ANCOVA) was used to test the results of the advertising experiment. Wearout, in terms of emotions felt (shock, fear and tension), attention paid, and expected speeding behaviour, did occur, with some fear patterns rapidly declining in effect in comparison with the other patterns of fear.