Cover: Decisions about production of petroleum are based on economic, social, ecological, and political criteria and frequently are highly contentious. In this issue, Czúcz et al. (pp. 948-956) discuss the anticipated peak and subsequent decline in production of petroleum, a phenomenon sometimes called peak oil. Few assessments of scenarios of environmental change incorporate limited supplies of resources. Czúcz et al. emphasize that using such scenarios to inform decision making may minimize undesirable effects of petroleum production on ecological systems and human communities.