This study examines marathon successions, which I define as top executive searches that are extended past the formal departure notice of the incumbent chief executive officer (CEO). Marathons should be used when search costs are high and when little time passes from when the incumbent steps down to when they leave the firm. Consistent with these predictions, marathons primarily follow surprise departures and forced turnovers. Marathons are also likely for firms operating in heterogeneous industries that face early tenure incumbent departures. These findings shed light on an increasingly prevalent form of succession and provide insight into the rationale and implications behind the announcement.