Clarifies the UNCED process and the Conference itself by assembling the key documents, including the final version of Agenda 21, and using them to recount how UNCED began, developed and finally, in Rio, came to fruition. Each document is preceded by analytical commentary.

Agenda 21 is a non-binding, voluntarily implemented action plan of the United Nations with regard to sustainable development. It is a product of the UN Conference on Environment and Development (UNCED) held in Rio de Janeiro, Brazil, in 1992. Its purpose is an action agenda for the UN, other multilateral organizations, and individual governments around the world that can be executed at local, national, and global levels. The "21" in Agenda 21 refers to the 21st century.