Although several approaches to transformational leadership training already exist, empirical research evaluating the effectiveness of these trainings is rare. In the presented work, team coaching was combined with training to enhance participants' transformational leadership in two different samples with an overall of 78 leaders. The experimental design compromised a pre- and post-test measuring with a 360° feedback questionnaire. In addition to transformational leadership, value congruence, proactivity and commitment were measured. Results, based on effect sizes and analysis of variance showed a positive effect of the training and coaching of transformational leadership in all samples: Furthermore, a positive effect of value congruence and proactivity was found. The postulated high effect of normative and affective commitment could not be confirmed. Implications of these results for practice and future research on leadership are discussed.