Introductory observations Part I. Setting the Framework: 1. The increasing interactions between foreign investment law and international environmental law 2. Conceptualising interactions 3. Synergies 4. Conflicts I - soft-control mechanisms 5. Conflicts II - adjudication mechanisms Part II. Normative Conflicts: 6. Normative priority in international law 7. Foreign investment and the international regulation of freshwater 8. Foreign investment and the protection of biological and cultural diversity 9. Foreign investment and the international regulation of dangerous substances and activities 10. Foreign investment and the climate change regime Part III. Legitimacy Conflicts: 11. Normative priority between different legal systems 12. Environmental measures and expropriation clauses 13. Environmental measures and non-discrimination standards 14. Environmental measures, stability and due process 15. Defence arguments based on environmental considerations Concluding observations.