This study analyses the competence gaps of lower-level managers in a typical manufacturing plant in Germany that had recently introduced a teamwork structure. Results indicate that the managers have difficulties with their new leadership-related tasks. Higher levels of leadership competence are found to be associated with better acceptance as a manager by superiors, but not by subordinates, better interaction with both subordinates and superiors, and with higher job satisfaction. Finally, a quasi-experiment shows that a combination of workshops and individual coaching had measurable effects on leadership competencies and partly improved identification with the managerial role. In terms of methodology, a new format of self-assessments is suggested for a more valid measurement of competencies. Key-words: Leadership skills, first line managers, training, experiment JEL-codes: C93, J24, M12 Acknowledgements We thank Nicole Guertzgen and Gaby Wunderlich for helpful comments and especially Sonja Kurz and Janin Ennes for important advice and support throughout the project.