Educating business students for ethical professional practice is a growing concern for both the corporate world and business education. Highly publicised scandals have pushed public trust in business to an all-time low, resulting in losses of customers and high employee turnover. Corporate and business education leaders have begun to press for more effective models for promoting ethical development in business education. This study examined the effectiveness of one such model, Deliberate Psychological Education (DPE), in promoting greater cognitive moral reasoning in undergraduate business students. Its significant, positive findings hold promise for the promotion of more ethical business professionals through preparatory classroom intervention. (Contains 4 tables.)