The entire environmental history can be classified into three stages:
- 1948- International Union for Conservation of Nature (IUCN).
- 1972-United Nations Conference on the Human Environment (UNCHE), Stockholm (Sweden). It is also known as Stockholm Conference. And United Nations Environment Programme (UNEP).
- 1975- Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES).
- The apporach before UNCHE was a mere informative approach and was based on dissemination of information about natural environmental conditions.
- 1985- Vienna Convention
- 1987- Montreal Protocol
- 1992- United Nations Convention on Environment & Development (UNCED).It is also known as the Earth Summit. It has 3 components: Convention on Biological Diversity (CBD), United Nations Framework Convention on Climate Change (UNFCCC) and Agenda 21.
- It encompasses developments under the three components of the Earth Summit.