What makes a “good boss” a good manager? This is a question that has always intrigued leadership and management theorists. Various models and theories of leadership have been put forward both to explain leadership success and to deliver recommendations for action to improve leadership practice or to solve problems. The overview model of effective and efficient leadership distinguishes between six partly interacting basic elements of effective leadership: First, a good leader should be aware of the external, and second, the internal influencing factors and influence them directly or indirectly in favor of his or her own organization. Third, both personal characteristics such as extraversion, conscientiousness, or intelligence and the fourth core element of motives and motivated action have an impact on leadership behavior. Fifth, a good leader needs instruments that increase the efficiency of the implementation, and sixth, a professional leader needs leadership competencies (do the right things), management competencies (do the things right), and entrepreneurship competencies that make effective and efficient leadership possible in the first place. Some guidelines for action are intended to help leaders put the theory into practice.