This chapter draws from the evidence produced in all of the other chapters of this book to categorise and explain the different types of standards that have developed within the field of environmental rights. It makes a distinction between what it describes as ‘outcome standards’ that prescribe specific outcomes for the environment and ‘governmental action standards’ that require governments to carry out certain actions to comply with the related standard. In providing this overview, it also demonstrates that there are certain ‘sources’ from which standards are derived whether they be at the international or national levels. It also indicates that environmental rights go through certain phases of development from the point of promulgation to the point of full maturity. It concludes by indicating some of the areas where further research in this field may be required and the ways that the international community can potentially further develop its understanding and application of environmental rights standards in the future.