Leadership has attracted growing attention among scholars and practitioners in public administration. With the rising availability of study results, however, it becomes increasingly difficult to keep track under which conditions leadership does or does not make a difference in the public sector. This study provides a meta-analysis of administrative leadership and various correlates that research has theorized as outcomes of leadership. The results of a multi-level random-effects meta-analysis based on 486 effect sizes from 151 studies show that correlations are stronger for the achievement of beneficial than for the prevention of detrimental outcomes, as well as for group- and organization-related than for employee-related outcomes. Moderation analyses reveal that leadership style, administrative tradition, administrative subfield, and methodological factors explain heterogeneity in effect sizes. Evidence for Practice Leadership in the public sector is positively and largely consistently related to beneficial outcomes, such as performance, and negatively associated with detrimental outcomes, such as turnover. Within the range of the analyzed leadership styles, it is not particularly important how public leaders lead - as long as they do lead. Laissez-faire leadership is confirmed to be a largely ineffective style of leadership. Leaders should be similarly cautious with the exercise of controlling forms of leadership. The broad range of leadership styles helps HR practitioners to adjust leadership trainings to the available talents and given settings. Public leaders may feel encouraged that there are many ways to become effective leaders. Administrative tradition matters, as the leadership-outcome relationship is less strong in some continental European as well as East Asian traditions than in the Anglo-American tradition. For example, this applies to transformational leadership.