U.S. Organizational Sentencing Guidelines provide firms with incentives to develop formal ethics programs to promote ethical organizational cultures and thereby decrease corporate offenses. Yet critics argue such programs are cosmetic. Here we studied bank employees before and after the introduction of formal ethics training—an important component of formal ethics programs—to examine the effects of training on ethical organizational culture. Two years after a single training session, we find sustained, positive effects on indicators of an ethical organizational culture (observed unethical behavior, intentions to behave ethically, perceptions of organizational efficacy in managing ethics, and the firm’s normative structure). While espoused organizational values also rose in importance post-training, the boost dissipated after the second year which suggests perceptions of values are not driving sustained behavioral improvements. This finding conflicts with past theory which asserts that enduring behavioral improvements arise from the inculcation of organizational values. Implications for future research are discussed.