Politicians are widely perceived to lose significance upon leaving office. Yet media accounts often highlight politicians’ legacies as a source of influence that endures even after they retire. This article assesses these contrasting views by investigating the substance, endurance, and significance of political legacies. We develop a theoretical account of legacies and their relevance to contemporary politics, emphasizing that in addition to “hard legacies” — concrete and enduring policy achievements — politicians often establish “soft” legacies — memories enshrined in the public’s consciousness. Soft legacies can be, but are not necessarily, tied to the substance of one’s hard legacy. We ground our theoretical account empirically by testing a series of observable implications using data from online discussion forums, original surveys of both citizens and political elites, thousands of former politicians’ Wikipedia pages, and a randomized experiment. We find that establishing a lasting legacy is a key motivation of public officials. More generally, our findings provide substantial evidence that legacies influence contemporary policy debates long after a leader steps down.