[This text provides an analysis and investigation of the most essential areas of environmental theory and policy, including international environmental problems. The approach is based on standard theoretical tools, in particular equilibrium analysis, and aims to demonstrate how economic principles can help to understand environmental issues and guide policymakers. Current topics including climate change, overfishing and integrated approaches to environmental policies are carefully analyzed in this framework, and a multitude of practical examples from various parts of the world is presented., This text provides an analysis and investigation of the most essential areas of environmental theory and policy, including international environmental problems. The approach is based on standard theoretical tools, in particular equilibrium analysis, and aims to demonstrate how economic principles can help to understand environmental issues and guide policymakers. Current topics including climate change, overfishing and integrated approaches to environmental policies are carefully analyzed in this framework, and a multitude of practical examples from various parts of the world is presented.]