Recent research has incorporated situational factors into assessment of risk. Working from a rational appraisal framework, however, these studies have not emphasized contextual features that might introduce motivated risk assessment. In the current study, participants (N = 40 male undergraduates) lowered their risk perceptions for STDs following the induction of a sexual motivation. In an initial baseline condition, participants estimated the risk of contracting STDs from partners with relatively high- or low-risk sexual histories. In a subsequent trial, participants repeated the imagery task while viewing photographs that were high or low in sex appeal. As predicted, participants reduced their risk perceptions when they viewed photographs high in sex appeal. The only necessary precondition was the presence of nondiagnostic information from which they could construct biased risk estimates.