One of UNEP’s fundamental mandates is to conduct accurate assessment and up-to-date reporting on the state of the world’s environment. The Global Environment Outlook (GEO) biennial report series contributes to the fulfillment of this role. GEO–1, published in 1997, provided a regionally focused, qualitative appraisal of key environmental issues and trends and relevant socioeconomic driving forces in all the world’s regions. GEO–2, published in 2000 presented a coordinated and comprehensive State of the Environment (SOE) overview at regional and global levels. It analyzed how underlying pressures (such as social developments) affect the land, atmosphere, fresh and marine waters, biological resources, and forests, and provided a separate presentation of environmental policy. This report, North America’s Environment: A Thirty–Year State of the Environment and Policy Retrospective expands on the North American regional contribution to the SOE chapter of GEO-3, published in May 2002. GEO-3 takes an integrated approach to SOE reporting and emphasizes the linkages between policy and the environment, past trends and possible future directions, and thematic areas. It also highlights the links among sectors (environmental, economic, social, cultural, etc). Its ultimate purpose is to connect environmental outcomes to activities, policies, and decisions. By providing a policy retrospective on progress made towards sustainable development since the 1972 Stockholm Conference on the Human Environment, GEO-3 will influence conclusions drawn at the World Summit on Sustainable Development in Johannesburg in 2002. The SOE component of GEO-3, and of this more detailed appraisal of North America, assesses the environment over the past 30 years by documenting how it has changed and how that change has impacted key human and environmental systems in the region. The policy aspect of this analysis seeks to explain how various policies have affected the environment in the past 30 years, to describe what is being done to lessen human impact on the environment and repair damage, and to evaluate the effectiveness of these policy measures.