One hundred and fifty-two heterosexual couples reported their actual and ideal duration of foreplay and intercourse, as well as their perceptions of their partners' desired duration of foreplay and intercourse. Further, participants reported the duration of foreplay and intercourse that they felt most men and most women wanted. Ideal length of foreplay did not differ for men and women. However, men reported a significantly longer ideal duration of intercourse than did their partners. The ideal duration of foreplay and intercourse were significantly longer than the actual duration for both genders. The women, but not the men, significantly underestimated their partners' desired duration of foreplay and intercourse. Further, both genders exhibited faulty stereotypes concerning men's but not women's ideal scripts. Men were seen as desiring a significantly shorter duration of foreplay and intercourse than the ideal reported by the men in the study. Both men's and women's perceptions of their partners' ideal duration of foreplay and intercourse were found to be more strongly related to their own sexual stereotypes than to their partners' self-reported sexual desires, suggesting that people rely on sexual stereotypes when estimating their partners' ideal sexual scripts. Men's and women's ideal scripts and men's and women's sexual stereotypes concerning the opposite gender's ideal duration of foreplay were found to uniquely predict the foreplay performance script. For intercourse, men's and women's ideal scripts and men's stereotypes concerning the duration of intercourse that women want uniquely predicated the performance script. We present potential reasons for the discrepancy in individuals' performance and ideal scripts.