The present study examined how young heterosexuals’ beliefs about the power of condom use to destroy their romantic ideals and to lead to negative implications affected both their intentions and their actual behavior of using and discussing the use of condoms with sexual partners. The extra predictive power gained from considering these beliefs, in addition to subjects’ beliefs concerning whether condoms reduced their risk of contracting HIV, was examined within the context of Fishbein and Ajzen's (1975) theory of reasoned action. One-hundred-and-two sexually active heterosexual students participated in the study. At the first wave of data collection, beliefs concerning the potential of condoms to reduce risk, to destroy romance, and to lead to negative implications were assessed, as were norms and intentions. Measures of actual behavior were obtained three months later for both regular and casual/new partners. The results of the study indicated that norms and beliefs concerning the risk-reduction effects of condom use were the primary predictors of intentions to use condoms. Subjects’ beliefs concerning whether condoms destroyed their romantic ideals or led to negative implications did not influence their intentions with casual/new partners, although emotional concerns played a minor role in determining intentions with regular partners. In contrast, these emotional concerns had a major impact in determining actual behavior for all partner types. Although intentions partially predicted behavior, beliefs about reducing risk, destroying romance and fear of negative implications had strong and direct influences on behavior, especially in the case of casual/new partners. Additional analyses revealed gender differences in the determinants of behavior. Females, in contrast to males, were less able to act in accord with their attitudes about using condoms to reduce their risk of contracting HIV, and were also less able to act in conformity with their subjective norms with less well-known partners. Although both males and females were similarly affected by more emotional concerns with new and/or casual partners, gender differences occurred in how these emotional factors affected behavior with regular partners. Implications of the finding that behavior is determined to a large extent by more emotional concerns that are not factored in ahead of time when formulating intent are discussed.