Given the increasing complexity of the strategic environment for future military operations, the necessity to retain hard-won officer expertise and knowledge and the imperative to address the demographic shift to an aging but active population, the U.S. Army must evaluate how to keep and develop selected senior field-grade officers for a 40-year career horizon. Senior talent for the purpose of this paper is defined as officers in the ranks of major, lieutenant colonel and colonel with 20 or more years of service.While a number of articles have focused on the outflow or retention of junior officers, more critical to the Army is stanching the tide of retirements of senior officers, who depart just when they offer the most value to the organization.1 In this vein, the paper first explores the time, experience and energy required to develop the knowledge and expertise of officers to perform effectively in complex joint, combined and interagency operations. It then shows how—with the population aging but having longer, healthier lifespans—progressive organizations seek to retain their valuable senior leaders and workers. It then highlights how the current military personnel system encourages officer retirements at the 20-year mark, when officers are reaching their experiential and knowledge peaks. The result is that the Army loses its senior talent just at the phase of highest significance and payback for the organization. In effect, the Army is foregoing its talent dividend after years of investment.The paper then offers four historical vignettes of military leaders who made high-level contributions in advanced age at the strategic, operational and tactical levels of warfare. Reflecting on the current human resource system, with its strict focus on “up or out” promotions and the possibility of 20-year retirements, this paper shows that under the current U.S. system, these selected warriors would have retired long before they could make their noteworthy contributions. The paper concludes with policy recommendations that would enable the Army to better retain, develop and tap its officer corps well beyond the current 20-year mark—for a potential 40-year career of service.