This study represents a new cross-disciplinary approach. A year-long art-based leadership intervention was compared to conventional leadership training using a random allocation design. The study has examined whether the art-based intervention has a stronger beneficial impact on leaders' development than the conventional program. Comparison was made utilizing leaders' self-ratings and subordinates' ratings of their leaders' frequency of expressed laissez-faire leadership and capacity to cope with stress. Our findings show a striking difference in the development between the two groups. In addition to displaying less laissez-faire behavior, the leaders in the art intervention appear to have improved their self-awareness, humility, and stress coping, while contrasting results were noted in the conventional group. These findings confirm the earlier results in our research.