Rio+20 has practical action as its goal, says the secretary-
general The message from Rio+20 is for practical action to
deliver existing targets. Scientists must identify and overcome
barriers to change. Sha Zukang, secretary-general of Rio+20,
held a press conference in Rio de Janeiro on 13 June, heralding
the start of the final phase of negotiations at the UN
Conference on Sustainable Development. He stressed that this
meeting is fundamentally different to the first Earth Summit,
held in Rio in 1992. Twenty years ago, the meeting produced a
legally binding document including conventions on biodiversity,
desertification and, ultimately, climate change. The Rio+20
outcome agreement, to be negotiated next week, has no basis in
law, said Sha — it is voluntary and political, and its goal is
practical action. This article is part of our coverage of
preparations for Rio+20 — the UN Conference on Sustainable
Development — which takes place on 20-22 June 2012. For other
articles, go to Science at Rio+20 Indeed, the a