Moral development has become an integral part in military training and the importance of moral judgment and behavior in military operations can hardly be overestimated. Many armed forces have integrated military ethics and moral decision-making interventions in their training programs. However, little is known about the effectiveness of these interventions. This study examined the effectiveness of a 1-week training program in moral decision making in the Swiss Armed Forces. The program was based on a strategy-based interactional moral dilemma approach. Results (...) of this quasi-experimental intervention study showed significant improvements in content-related (moral and instrumental awareness, quality of moral information processing, development of compensatory actions) as well as process-related (situational analysis, development and evaluation of alternative solutions, justification of decision) aspects in moral decision making. Results of a follow-up test indicated positive long-term effects with regard to moral and instrumental awareness and process-related aspects. Findings are discussed, and consequences for leadership development programs and further research are explored. (shrink)