The past, present, and possible future of the agency designed to act as “the world's environmental conscience.” The United Nations Environmental Programme (UNEP) was founded in 1972 as a nimble, fast, and flexible entity at the core of the UN system—a subsidiary body rather than a specialized agency. It was intended to be the world's environmental conscience, an anchor institution that established norms and researched policy, leaving it to other organizations to carry out its recommendations. In this book, Maria Ivanova offers a detailed account of UNEP's origin and history and a vision for its future. Ivanova counters the common criticism that UNEP was deficient by design, arguing that UNEP has in fact delivered on much (though not all) of its mandate. Drawing on extensive interviews she conducted with UNEP's past and present Executive Directors, staff, and two former UN Secretaries-General, Ivanova provides rare insight into the organization's functioning. She shows that UNEP was able to resolve problems and launch important processes when it had financial and political support. Its failures and limitations came when the environment slipped as a priority, leadership faltered, and connectivity was challenged. UNEP's fiftieth anniversary, Ivanova argues, presents an opportunity for reinvention. She envisions a future UNEP that is the go-to institution for information on the state of the planet, a normative vision of global environmental governance, and support for domestic environmental agendas.