As environmental problems become harder to regulate and public funds available for environmental protection decline, more people are looking to private investment as a tool for helping to improve environmental performance. This course explores the foundational legal aspects of these initiatives, both opportunities and limits. It starts with an analysis of the goals of private investors—as a way to target efforts to change their decisions. It then moves to a review of the legal frameworks within which investors operate (property and tax law), as well as the legal tools that investors use to order their activities (contract law) and that governments use to address market failures (liability, regulation, information and market mechanisms). The course concludes by examining efforts to use combinations of these legal tools to expand private investment in environmentally superior goods, services and operations.