Increasingly, public administration in the United States operates in a densely interconnected international system in which local decisions and actions may trigger global repercussions—and vice versa—and the fate of communities in one region is bound to the choices of decision makers elsewhere. Administrative actors have become enmeshed in a complicated, interwoven pattern of governance in ways that shape actions, issues, and opportunities for influencing administrative agencies at national, state, and local levels. These developments call for a critical reappraisal of our inherited notions of governance, management, and accountability. Terrorist tragedy and responses to it call attention to these themes, but they apply broadly across the spectrum of governance challenges. To demonstrate this point, we analyze some implications of transnational governance for the institutions and practices of U.S. public management, with particular attention to another subject: environmental policy and management. A conclusion is that the public administration community must adjust traditional practices to facilitate the effective management of the global processes that, in turn, reshape the world.