Led by the Affordable Care Act, the U.S. health care system is undergoing a transformative shift toward greater accountability for quality and efficiency. Academic health centers (AHCs), whose triple mission of clinical care, research, and education serves a critical role in the country's health care system, must adapt to this evolving environment. Doing so successfully, however, requires a broader understanding of the wide-ranging roles of the AHC. This article proposes a conceptual framework through which the triple mission is expanded along four new dimensions: health, innovation, community, and policy. Examples within the conceptual framework categories, such as the AHCs' safety net function, their contributions to local economies, and their role in right-sizing the health care workforce, illustrate how each of these dimensions provides a more robust picture of the modern AHC and demonstrates the value added by AHCs. This conceptual framework also offers a basis for developing new performance metrics by which AHCs, both individually and as a group, can be held accountable, and that can inform policy decisions affecting them. This closer examination of the myriad activities of modern AHCs clarifies their essential role in our health care system and will enable these institutions to evolve, improve, be held accountable for, and more fully serve the health of the nation.