The document discusses the relationship between human societies and the natural environment. It notes that while nature always posed risks, human societies have now developed the ability to significantly modify their environment quickly. This introduces new risks from uncoordinated human activities that can impact natural systems. The document examines different types of risks from nature, society, and problems of social cooperation/coordination. It also discusses the assessment of environmental risks and different approaches like cost-benefit analysis and risk management. Property rights regimes and common resource issues are evaluated in the context of sustainability and management of exhaustible resources.