An environmental management system (EMS) is a systematic approach to identifying and managing an organization's environmental obligations and issues that can complement many aspects of the National Environmental Policy Act (NEPA) review process. An EMS is a "set of processes and practices that enable an organization to reduce its environmental impacts and increase its operating efficiency." As such, EMS is a promising means of bringing progressive private-sector environmental management techniques to federal agency management. The growing use of EMS in federal agencies has been fostered and supported by a series of Executive Orders and policy statements. To date, the experience has been somewhat limited and, typically, federal facility-specific. However, the expanded use of EMS not only promises to improve the environmental performance of federal agencies but to help federal agencies focus on improvement of their environmental performance, which is--under NEPA--an integral component of every agency's mission.