PurposeThe purpose of this paper is to examine whether, when teaching professional ethics, the educational interventions have any effect on improving students' moral decisions. One method often used to measure change is the well‐established defining issues test – an American test based on Kohlberg's stage theory.Design/methodology/approachUsing this test, two before‐and‐after studies were carried out on cross‐cultural cohorts of first year computing undergraduates which both received the same lectures, debates and moral‐decision‐making exercises.FindingsOne study showed a significant increase in moral judgment whilst (...) the other showed a decrease. Both studies indicated mean scores far below the American averages.Research limitations/implicationsAs both studies involved relatively small sample sizes, the results are indicative rather than conclusive. However, they bring to light issues associated with the test, in both American and non‐American research, indicating that lower than average mean scores could be due to cross‐cultural and situational variations.Practical implicationsThe paper questions the premise of stage theory as a method for measurement within a cross‐cultural context; and the usefulness of measuring one component of moral development in isolation.Originality/valueThe paper proposes that tests based on more discipline‐specific skills, rather than stage theory, would be of greater use in evaluating student levels of moral development. (shrink)