The authors investigated the psychometric properties of a 22-item scale that measured respondents' perceptions of their ability to refuse sexual intercourse, question potential sexual partners, and use condoms. Two hundred twenty-one male and female undergraduates completed an anonymous questionnaire that measured a wide range of constructs. The scale exhibited good internal consistency, and convergent validity was demonstrated for 5 sexual behavior items (number of sexual partners ever and in the past 3 months, condom use in past 3 months, at last intercourse, and in the future). The instrument appeared to be free of social desirability bias and was reliable and valid for assessing college students' self-efficacy for protective sexual behaviors. College healthcare professionals could administer the instrument to help students determine their levels of self-efficacy for engaging in self-protective behaviors and identify domains in which they may need to improve their skills to reduce their risks of acquiring a sexually transmitted disease or having or causing an unplanned pregnancy.