<Tr> <Th> ISBN </Th> <Td> 978 - 92 - 1 - 100509 - 7 </Td> </Tr> <P> Agenda 21 is a non-binding action plan of the United Nations with regard to sustainable development . It is a product of the Earth Summit (UN Conference on Environment and Development) held in Rio de Janeiro, Brazil, in 1992 . It 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 . </P> <P> The "21" in Agenda 21 refers to the 21st Century . Although it is also the area code for Greater Rio de Janeiro, plus Teresópolis and Mangaratiba in the countryside . It has been affirmed and had a few modifications at subsequent UN conferences . Its aim is achieving global sustainable development . One major objective of the agenda 21 is that every local government should draw its own local agenda 21 . </P> <P> Agenda 21 is a 350 - page document divided into 40 chapters that have been grouped into 4 sections: </P>

Write the most important objective of agenda 21
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