This research examined cross-cultural differences in business-related ethical perceptions. Subjects were attending one university in either the US or Japan. This study found significant differences between the ethical perceptions of US and Japanese accounting students in a whistle-blowing scenario, particularly with respect to individualism. This enhances our understanding of cross-cultural ethical differences in a manner suggested by Butler et al.(1991), who cited the importance of documenting existing ethical perspectives of individuals from different countries and collecting evidence on the determinants of such perspectives. Since the subjects in this study have not yet received any formal workplace training, it is more likely that observed differences in ethical perceptions are due to cultural differences. One implication of the results is that businesses with multinational operations should perhaps consider the cross-cultural effectiveness of their systems of internal control.