Millhoff, Catrin2020-10-072020-10-072019http://hdl.handle.net/2003/3976810.17877/DE290R-21660This dissertation examines the influence of instrumental leadership in the framework of the extended full-range of leadership model on employees’ reactions to change. Positive employee reactions are regarded as crucial for the success of organizational change processes. Besides, current research leaves many questions about effective leadership in the context of change unanswered. Therefore, the main goal of this dissertation is to investigate how instrumental leadership as an extension of the full-range of leadership model can foster employees’ positive change reactions. Within a framework model that links leadership behaviors with differentiated change reactions, three empirical multimodal studies using a triangular approach contribute to a deeper understanding of the impact of instrumental leadership during change. The first study analyzes whether instrumental leadership is a theoretically and empirically meaningful addition to the full-range of leadership behaviors by investigating interdependencies among the leadership behaviors and their change-related consequences. In the second study, the mechanisms and conditions of how instrumental leadership affects employees’ individual and team change reactions were examined in more detail. Finally, in the third study, a training for the two change-promoting leadership styles of the model – instrumental and transformational leadership – was developed and evaluated. In summary, this dissertation extends the leadership literature by demonstrating that instrumental leadership plays an important role in the change context. This strengthens the theoretical and empirical relevance of instrumental leadership as part of the extended full-range of leadership model. The main findings are that transformational leadership only has a positive influence on change support if instrumental leadership is highly developed. The results thus question the change-enhancing effect of transformational leadership on its own and expand the literature by confirming the integrative view of the extended model in times of change. Furthermore, it was shown that instrumental leadership has a positive effect on team change success and individual change support through cognitive attitudes in the team. The indirect effects are reinforced by the cognitive attitudes of the leader. Moreover, instrumental leadership can be actively enhanced by training interventions, and it became apparent that the positive development of leadership behaviors caused by the training led to an intended variation in employees’ change reactions.eninstrumental leadershipextended full-range of leadership modelchange reactionschange commitmenttraining instrumental leadership300doctoral thesis