As much as environmental problems manifest themselves as problems with the natural environment, environmental problems--and their solutions--are ultimately social and behavioral in nature. Just as the natural sciences provide a basis for understanding the need for environmental policy and informing its design, the social sciences also contribute in significant ways to the understanding of the behavioral sources of environmental problems, both in terms of individual incentives and collective action challenges. In addition, the social sciences have contributed much to the understanding of the ways that laws and other institutions can be designed to solve environmental problems. In this paper, we distill core intellectual frameworks from among the social sciences that scaffold modern environmental policy in industrialized country contexts—focusing on key contributions principally from political science, economics, psychology, and sociology to the analysis of environmental problems and their solutions. These frameworks underlie how environmental problems are defined at multiple scales and the conceptualization and empirical testing of policy solutions that seek to shape human behavior in ways that improve environmental quality and promote sustainable economic growth. With the planet facing continued environmental threats, improving environmental policy decision making depends on the insights and frameworks of social science research in addition to those of the natural sciences.