Abstract.Although there exists a plethora of studies on the determinants and consequences of facial attractiveness, there exists little research on how within-individual evaluations of facial attractiveness are impacted by knowledge of a person's sexual history and the duration of the relationship they seek. Using a pre-post design, participants rated individual faces for attractiveness, and then re-evaluated the faces accompanied by a fictitious online dating advertisement, manipulated for the models' sexual history and desired relationship duration. We found that women, more than men, were impacted by this knowledge and that desired relationship duration influences the direction of change while sexual history influences the significance of the effect. One week later, participants were presented with the same faces and asked to recall the prior information. Participants recalled more information for sexual history than for desired relationship duration with an overall mean accuracy of 64.4%. These findings are discussed using the conceptual framework offered by evolutionary psychology, particularly mate selection theory.Keywords: sex differences, facial attractiveness, memory, sexual experience, romantic relationships Evolutionary psychology provides a framework in which to explain sex-based differences in mating preferences. One aspect of evolutionary theory, sexual selection, suggests that mating strategies are solutions to sex-specific adaptive problems (BUSS and SCHMITT 1993). Women and men must confront distinct adaptive problems, such as how to allocate their time and effort with respect to