To prevent unethical behaviors, organizations are developing or revising their ethical codes or implementing some ethical programs. Although there are many studies investigating the effectiveness of ethical programs
on unethical behaviors in the literature, these studies have mainly explored the effect based on the existence of ethical codes, leading to conflicting results. Therefore this research is used the perceptions of ethics program follow-through (EPFT) for the measurement of the effectiveness of ethics programs to detect the effect accurately. The research examines the effect of EPFT on the relationships between ethical leadership, ethical climate and unethical behaviors. Results of the survey which is applied to 450 employees working for 20 large companies having formal ethical programs are analyzed by SPSS and AMOS programs. The analysis results reveal that EPFT has moderator effect on the relationship between ethical leadership and unethical behavior increasing the effect of ethical leadership on unethical behavior and that EPFT has moderator effect on the relationship between ethical leadership and ethical climate dampening the effect of ethical leadership on ethical climate. These results show that the effectiveness of ethical programs is related with organizational ethical structure. Limitations of the study and implications of these findings are discussed in detail.