This article presents an experiment examining the effects of stimulus complexity on consumers' aesthetic, preferences. The results suggest that preferences for visually complex product designs tend to increase with repeated exposure, while preferences for visually simple product designs tend to decrease with repeated exposure. In addition, the results suggest that perceived complexity partially mediates the exposure-preference relationship. The authors discuss implications of these findings for market researchers conducting aesthetic product design concept tests, as well as more basic research on the affective impact of repeated exposure.