While most people associate a leadership position with experience, wisdom, and maturity, the reality in many companies is now different: Employees are increasingly being led by managers and supervisors who are significantly younger than they are. This can be problematic for both sides. Scientific theories, for example, assume that this results in a violation of societal and organizational norms that can be associated with negative consequences for both employees and managers. However, the existing data on this question is still rather sparse. In this chapter, we examine the reasons for these rather skeptical assumptions in more detail. In addition, we present new measurement tools as well as concrete recommendations for action and case studies that can help both the young leaders and the HR managers in companies, who prepare young supervisors for the upcoming leadership task, to deal with problems, to recognize the young-leads-old constellation, and—ideally—then also to avoid it.