A man’s misperception of a woman’s momentary level of sexual interest can increase the risk of sexually aggressive behavior between acquaintances. A better understanding of these basic perceptual errors may inform future prevention efforts on college campuses. My dissertation assesses whether men’s ability to accurately perceive women’s changing levels of sexual interest over time is related to 1) women’s normative attractiveness or clothing style, or 2) men’s endorsement of rape-supportive attitudes.