Unique among environmental treaties, the Rio Declaration was adopted by all member states within the United Nations as the result of the Rio Conference and, as pointed out in Pierre-Marie Dupuys contribution, the firstand until now the only conference that can be called.the Earth Summit. This factor alone should persuade all those interested in, or professionally involved in the complexities of environmental issues, that that this book is one of the most important and authoritative contributions to environmental research and comment currently available. Certainly it should emerge as an essential acquisition for every environmental lawyers professional library.